During a routine traffic stop, an officer arrests a shop-lifting suspect named Amanda Millerd. After she is taken to the station and booked, Ali and Jill realise that her fingerprints match those of Holly Tarrow, a prostitute believed to have burned to death on September 6, 1982. Although initially Holly maintains her identity as Amanda and claims she's in the city with her husband Grant and son Ethan, she soon admits that she is Holly, and that while at a party with her then-boyfriend Wesley Belmont, Amanda was accidentally killed by the owner of the house.

The squad discovers what happened with Billy Wells and Michelle Ripley.

Cold Squad is convinced they have the necessary ammo to bring down killer Dean Bulmer, and Nicco goes so far as to promise the family of one of his unlucky victims that it's in the bag, but when a body found proves to belong to the man Bulmer is on trial for killing, the Squad realises that Bulmer has been fingered for the wrong murder, and it comes down to the moral question of whether to lie to keep a vicious killer in prison, or to tell the truth and have him set free.

When Ali's testimony results in the release of a killer (Dean Bulmer), Coscorella takes it too seriously and makes catching Bulmer his sole goal, much to the displeasure of homicide detective Len Harper. Nicco is furious with Ali and believes she should have lied to keep Bulmer in jail, and tries desperately to keep the father of one of the victims from taking justice into his own hands. Cold squad is in danger of being closed down, and the officers absorbed into the homicide division.

Nicco and Ali investigate the unsolved murder of Jeff Steeves, AKA. Vulse G, after a car is found underwater. The car leads them to an elderly woman named Clarice Fry, which eventually leads them back to her grandson Timo, who has a connection to Jeff's former manager, Desecrate. Mickey is assigned to work the case of Lester Graham, a gambler who owed $20,000 to an on-line gambling company who is rumored to be very violent in their collection methods. Mickey is upset when Bailey asks her to San Francisco then takes his wife instead, but shrugs it off to Nicco.

Harper searches desperately for his missing daughter, praying that he will find her before it is too late. Sam has the perfect suspect, an well-known surgeon, but the only witness against him is very unstable.

The Squad continues to work on the Ambleton case, feeling they've hit a break when they arrest a former student, Shelley Mack, who tells Mickey and Ali about parties that used to be held in the Love Shack, with Desmond Cage in attendance. Nicco tries to help Billie beat her addiction and get away from her pimp, but when he can't find her a place in a rehab clinic he tries to help her go cold turkey. Andy has no choice but to turn over the Ambleton files and all evidence on Desmond Cage when a request from higher up comes down.

Ali and Frank investigate a rock star accused of murdering a woman who fathered his child -- a woman he swears he never even met. While trying to figure out what Nicco does with his time, Mickey investigates the case of a woman who comes in and tells them her husband killed a baby.

As an investigation into a 20-year-old killing spree continues, the Cold Squad is rocked by murder and internal strife.

A 12 year old case where a murdered woman's death matched the M.O. of a now-convicted killer seems to be yet another victim. Until investigation shows the killer couldn't have done it. He was already in prison. McCormick and Logozzo try to find who was the original killer and who was the copycat. This two-part episode introduces Inspector Simon Ross.

On August 2, 1982, two young boys disappeared. When the body of one was found later, they used the child's backpack to help identify him as Benji Harding, the son of a firefighter. Sixteen years later, a former co-worker of Harding's sees a computer screensaver featuring pictures of a child he swears is harding. Simms calls Lloyd Mastrowski in to work on the case, since he worked the original, and it isn't long before they realise the body belongs to Christopher Kowalchuk. During the course of the investigation, suspicion turns to Lyle and Grace Burgoyne, a family whose son died sixteen years ago in a fire when Harding was unable to save him. The case has political implications because the Kowalchuks spear-headed numerous missing childrens' campaigns after their son went missing, only to finally be told there was never any hope.

With her life in shambles and Det. Logozzo in the hospital after the warehouse shooting, Ali spends most of her time with her partner. Simon is somewhat involved in the investigation, but most of this episode is used to introduce the new characters in the series as they try to solve an old murder that has connections to the boy Ali hit. It turns out the youngster had a weapon and it is tied to the murder. Meanwhile, Simon tries to patch up things between him and Ali and learns where Ali was when she was supposedly on vacation ... she had an abortion.

After Ali hits a young boy with her car after having a fight with Simon, she soon finds herself not only fighting to prove her innocence, but also fighting to get her job back, which she was stripped of without her knowledge while on vacation. Cold Squad has been turned into a provincial task force, and the only member of the old guard left is Logozzo, so Ali has to prove herself to Coscarella, the new sergeant in charge.

Ali and Logozzo investigate the case of Stephanie Jordan, a debutante who disappeared four years earlier and was presumed, but never proven, to be dead. Her husband, reporter Turner Jordan, is their prime suspect, and he puts a serious crick in the investigation by making a televised plea for anyone with information to phone the police. Logozzo is frustrated because his daughter from his first marriage is not only getting married outdoors, she has invited his third ex-wife Vivian, with whom Logozzo does not get along.

Nicco is in the hot seat when his friend Gus (another cop) is shot and killed, and a local drug dealer, Hoppy, is charged with the murder. Ali and Mickey investigate when a thief about to be released from jail confesses to a murder, believing he simply wants to remain in jail.

Ali and Inspector Ross return to the Squad room in formal dress, their conversation indicating that Ali accompanied Ross on an official function, but there is indication that Ross is interested in her. Meanwhile, Logozzo has turned up some evidence of an old murder and the victim leads to a disappearance of Rev. Douglas Somerset. Somerset had left to go on mission trip in his own plane, but the plane never took off. Speculation is that Somerset was murdered by a hooker. The odd thing was that once the family had reported the missing man, they never checked back to see if the police had turned up anything. The circumstances of the man's disappearance causes Ali to think about the loss of her father, a pilot, in a plane crash. His body was never recovered.

A standard pick-up for the drunk tank marks the start of a 34-year old cold case involving three men who were involved in the murder of a beautiful woman. The drunk is carrying her dress and tells a bizarre story of murder that involves his college roommates who are now prominent professionals in business. McCormick is relentless in the case and impresses Ross with her work. As she struggles with the case, Ross tells her as he leaves that he will be thinking about her as his head hits the pillow.

When Dana Hughes comes into the station to report to Mickey that her estranged husband murdered two hookers three years earlier, they investigate, and when the young woman is beaten, Mickey blames herself because she warned the husband to stay away from his wife. As the case goes on, Dana brings in more and more evidence against Wayne, but what Mickey doesn't know is that someone is pulling all Dana's strings. After modeling for the cover of a local magazine, Ali considers a transfer to Ottawa, where she would be working in a joint American/Canadian anti-terrorist task force. Dan forms a partnership with his uncle so he and Vanessa can go with her, but Ali's mother's past is going to stand in her way. Nicco is forced into a meeting with department psychiatrist Leanne Walker in regards to the death of André, the pimp of a young hooker named Billie that Nicco had gotten involved with and helped clean up her life.

When the squad investigates the murder of an abortion doctor, old wounds are re-opened for the team.

The squad tries to break a former officer preparing to leave the country. They're convinced he killed two people while his young daughter, dying of cancer, watched from the back of the car.

Four years earlier, Rikki Stanfield lied to Ali about what she remembered the night that she and her best friend, Michelle Dorn, were attacked to get Ali to leave her alone. When Rikki starts to remember what really happened she begs Ali to re-open the case, and despite Logozzo's feeling that Rikki is a few bricks short of a load, Ali takes on the case.

Christopher Gerald Williams was ten when he was taken from the bedroom he shared with his seven-year-old brother Joey in 1977. Twenty years later when another body is found, Tony realises that David Sawyer was killed in a way very similar to young Christopher, and Ali joins forces with Iredell to uncover the killer. After doing DNA tests, the squad realises that the same man killed both boys, and they begin investigating Victor de Jarre and Jacob Knewling, who were suspects in the first investigation. Ali tries to get what she can out of Christopher's now-grown brother Joey, who has become an alcoholic.

After getting himself arrested while on a camp-out in the United States, Harper goes undercover to smoke out marijuana traffickers and in his discussions with the squad soon realises that minor dealers have been dying mysteriously. His objectivity is seriously challenged when he finds himself falling for Lila, the innocent sister of one of the main suspects.

Nicco is finally back on general duty, and his first major investigation involves a missing girl named Mimi whose mother has been searching for her. Ali continues to meet roadblocks in her quest to learn who truly killed Khallid Fulani, and makes a decision that will change her life. Len is determined to find Sonia's killer no matter what, and finally tells Wanda the truth about the affair.

When Nicco investigates the death of a female tree planter that took place thirty years ago, his best suspect is a well-known humanitarian Ian Northby, and Nicco soon begins to regret getting involved in the case, and finally realises that he doesn't belong in the Squad, but back on the force. After having an affair for months, Len gets antsy when Sonia gets involved in an undercover prostitution bust. She promises to quit if he will leave Wanda for her. He finally does, just as Sonja is being injected with a massive dose of heroin by the American pimp she's investigating. At the urging of the daughter of convicted murderer Abdul Rhaman, Ali agrees to look into the crime he was convicted of, the murder of Khallid Fulani. When she starts searching, she learns that Fulani never truly existed, and C.S.I.S. has seized all the files.

Ali and Len re-open the case of a corrupt stockbroker, Jack Dolan, who had stolen millions from his clients. When they begin questioning the clients, they learn that Jack and his then-wife Arlene were members of a club of swingers. Originally they look at jealousy as a motive, but no one seems to have been angry about any of the relationships. Len also finds himself interested in the lifestyle of a swinger, which Wanda shoots down immediately. Nicco is finally finished his counselling sessions with Leanne, and when she calls him to her home he goes over and spends the night. The next day Leanne starts talking about their 'relationship', and when Nicco tells her she's moving too fast she accuses him of using her for a one-night stand.

A self-help lecturer may have influenced a prison guard to murder a prisoner.

Ali and Frank are assigned to find out who murdered plastic surgeon Marvin Michaelsen after a drug dealer identifies him as the man who removed his fingerprints, but the tension between the two soon ends up taking a higher priority than the investigation. Nicco and Mickey work together on the case of Dermot Wells, a garbage collector that is believed to have murdered his former co-worker, and make a bet on how soon they'll get a confession.

Marcey Bennett was only fourteen when she was found raped and murdered in April of 1986. The gardener, Matthew Dalton, was arrested for the crime and later confessed. While cleaning out some of the junk in Sam's office, Max finds a videotape showing the investigation and when he and Ali realise how horribly the scene was contaminated, Ali decides to take another look into the case. With the focus on a former cop turned judge, Lance Giffen, Tony accuses Ali of being out to get all cops, still not over what happened with Vince Schneider. Ross decides to let Ali take an unofficial look, but warns her about Logozzo's drinking.

Ali begins second guessing her actions on a past cast when lawyer Paul Deeds approaches her with the suggestion that Bryn Fulford, a man Ali and her former partner Desoto put away for murder over a decade ago, was really innocent of the crimes. Sam takes an active interest when Ray can't put aside the on-the-job shooting of suspected cop killer Boone Judson, who just happened to be the long-time nemesis of some strike force members that Sam has history with.

After comic book Steve Baker owner is shot at, Ali takes another look into the disappearance of a young woman named Thora who everybody believed Steve had murdered. At Ali's request, Ray begins 'protecting' Steve from Thora's father David and former boyfriend Mark while trying to uncover some dirt on him. Harper is pre-occupied with his wife having kicked him out of their home, and when she and her parents cut him off from seeing Eva and Kassia, Harper finds his world falling apart.

Frank investigates the death of a forgotten war hero. Ali applies to become a Big Sister after questioning her value as a cop

When a camp counselor offers evidence that three children who died in a boating accident at camp thirty years ago were actually murdered, the Squad investigates the claims. Ali initially goes off what Goren Berkland is claiming even though there is only his word to go on, until she discovers that he lives in a mental institution and is only occasionally in touch with reality.

When a young woman dies mysteriously before what everyone assures Cold Squad was a guaranteed win in a nationally televised singing contest, the group investigates only to learn that the singer's worst enemies may have been closer to home than she thought.

When the squad identifies a body in the field as belonging to a young man named Joshua Stokes, Andy personally takes the news to his old friend Preston, the young man's father, and catches him in the middle of a messy divorce. His investigation soon takes him into the world of male prostitution, where he soon finds a young straight man named Rick who is trying to make a few bucks willing to give him as much information as he can. Meanwhile, Ali's friends at the station are determined to find her a man, but a disastrous bar setup and a matchmaking barbecue at Len's confirm that the only thing Ali needs a man for is occasional relief.

When Ali is on her way back from a routine prisoner transfer, Winslow accidentally crashes the car (somewhere off highway five between Clearwater and Little Fort), leaving Ali and himself relying on the prisoner they're transporting, Paul King, who is accused of the brutal murders of two men. Ali and the prisoner both beg Mitch to uncuff Paul so that he can help them (Ali has a spike through her arm and Mitch has suffered heavy internal injuries), but Mitch absolutely refuses. When Mitch finally dies from his injuries, Ali begins to talk to the prisoner, who maintains his innocence in the murders and swears that he's only out to save the environment.

Sam finally gets a case of her own -- the three year old beating death of a homeless man -- which leads the squad to a company that tapes homeless people fighting to sell on the Internet.

Still torn up over his separation from Wanda, Len relentlessly pursues a serial killer as Wanda seeks sole custody of their two daughters.

The murder of gay-basher Ken Reegan on Davies street prompts the squad to re-open the three-year-old murder of another gay-basher, Terrance 'Tron' McLean. Nicco and Len connect with homicide to investigate the case, and Len can't keep his personal prejudices out of the case, which involve working with a gay officer, Luke Darling. Mickey uses the department's new computer toy to help Ali with a 10-year-old arson case. It eventually leads Ali to Boris Delgado, a former troublemaker who found religion after the first fire but was unable to escape his past.

After Mitchell Huston dies under mysterious circumstances at the Green Abbey hospice, Father Geddes points the finger at Dr. Sarah MacInnis. MacInnis ends up arrested, and Maz tells Ali he thinks they have an open and shut case, especially now that they also suspect Sarah of killing her husband Gavin (Mac) years earlier. Ross keeps trying to get Ali to move on the Seniuk case, and even though Tony learns that the real Nancy Seniuk was born in 1922 and died two years later, Ali lies to Ross when he asks her about it. She also suspects his motives after Malcolm, who sees them having dinner together, warns her against romance in the workplace.

After a taxi driver reports a passenger who seriously gave him the creeps with his misogynistic views on women, Ali decides to look into it, and the trail leads her to Ian Summerhill, a dentist who had dated the first missing woman and had been dating the woman found a couple of days after the cabbie came in. Sam tries to investigate Summerhill's dark side and heads back to her old work place, where girls entertain men for money. Ali's relationship with Paul is threatened when Ian shares some stories of Paul's mis-spent youth with her, and she wonders how accurate they are.

The squad helps Moscow police probe a Russian hockey star's death.

When Ali hears that suspected killer John Watts is about to be extradited for trial in Texas, she's determined to get him convicted in Canada of the murder of Gus Johansson to save him from the dealth penalty, which she does not agree with. When Ali and Agent Mitchell (who is there to extradite Watts) try to question the suspect, he grabs a cop's gun and holds Ali hostage. Nicco is accused of sexually assaulting the police psychiatrist, Leanne Walker, but maintains his innocence to Andy because what they did was consensual. When he tries to talk to her, she makes it clear that if he wants her to drop the charges, she has to come back to therapy with him. Mickey agrees to check an apartment for Christine's replacement, Denise, and learns that the building has had a large number of rapes recently.

When a twelve-year-old girl disappears from her bedroom, Ali and Ray infiltrate the world of pedophiles in a desperate attempt to find her.

The squad re-investigates the murder of a well-known philanthropist at the request of the son who is believed to have murdered him. Nicco helps Mickey when she's suspected of murdering Bailey Gallanson's wife.

A count of the corpses in storage at a police training facility leads to a murder investigation.

The squad gets involved in the world of street racing.

A public outcry follows the brutal murder of a prostitute, which resembles several unsolved killings.

A tax-evasion case leads to an investigation of a prostitution ring and murder.

Ali and Tony find a corpse hidden in a building that turns out to be Edmund Kritch, an anti-radical that disappeared over twenty-five years ago. While Tony investigates former members of a radical group known as Code Red, Cortez is convinced that the dead man's boss is behind everything, and Ali suspects the dead man's former girlfriend. Nick and Ali finally take their flirtation to the bedroom, where Ali is shocked to learn that Cortez was there first.

Courts rule evidence in a murder case inadmissible prior to a retrial.

When one of Reid Logan's five wives shows up at the station, she tells Frank and Nicco that she believes the death of Louise Logan, Reid's only legal wife, four months ago was foul play. While investigating, Nicco is intrigued by Libby, the most recent wife who took Louise's place as Reid's only legal wife. Mickey is beaten up by a suspect in the brutal deaths of the Williams' and their baby, and although Ali tries to help her, she soon crosses the line in her zeal to get Price and his partner.

Frank and Nicco are stripped of their badges over the drug probe.

Two robbery suspects take hostages in the squad room.

A case from Pawlachuck's past comes back to life and forces him to face up to some personal demons he thought he had escaped for good and from this he learns a few things about himself in the progress.

Mickey partners up with an old flame to solve a case.

The team investigate the death by drug overdose of an up-and-coming artist.

Harper can't let go of his obsession with Viveca Wells. He is convinced that she murdered her last husband, and when he learns she's engaged to be married again, he tries to warn her fiancé, Richard, who tells Harper that he knows all about her past, and he's okay with it. While researching the case with Ali and trying to fight his own attraction to Wells, he learns that Richard has been the man in her life all along. Nicco is upset because in the six weeks since he's been off of suspension, he hasn't worked a single case. Ali finally throws him a bone by having him interview a prospective witness in the case of a racially motivated murder and while Nicco gets the man to ID the suspect, he's not happy with it.