Ricky and Stephen debate the merits of 20th century inventions with Karl; the guys introduce 'Monkey News.'

Stephen shares a news story about 42 midget warriors who were mutilated by a single lion in a Cambodian ring fight, as well as the latest email from a fan, Paul "The Party Animal" Parker, who describes a Serbian man who invented a sex machine for women. Karl ponders how to avoid being conned into donating to charities. That conversation segues into a discussion of sex and butt plugs. A dialogue about America's first nudist organization leads Ricky to critique naked gym jocks, inspiring a revelation from Karl. The guys debate if there is ever a good time to eat the penis of a kangaroo? In Monkey News: A pair of chimps are shot to death after viciously attacking a male visitor to an animal sanctuary, targeting his nose, limbs and genitals.

Adding to his wish list of improbable inventions, Karl offers up a serum that ages dead people backwards. Also up for discussion: Do African families really want goats as charitable gifts? Is a space flight worth the money and effort? If you could have any super power, what would it be? How rare is it to see a Chinese homeless person? In "Monkey News," a Moscow network fired so many employees it had to hire a chimp to host a talk show, with Cher as one of the guests.

Karl admits he's getting a face rub at a spa, but frets he'll end up getting an enema as well. Also: A discussion about the customs of undocumented tribes in New Guinea. Ricky and Karl's recent trip to an antiquities store, where Karl wondered, "What's the newest thing you've got?" An e-mail from an Australian fan insisting there are dangerous armed dolphins ready to do battle. In "Monkey News," Karl recounts the marital regrets of a sympathetic zookeeper who brings home a lonely monkey

Karl answers questions from fans; Karl deciphers the true meaning of sayings; Karl’s New Year’s resolution; “Monkey News.”

After receiving a fan letter asking what body part he could live without, Karl recalls when he tried to wash the dishes without using his thumbs. Other fan mail questions: If Karl could be anyone in the world, who would he be? What does he think of the philosopher Descartes? What does he make of the saying “a stitch in time saves nine”? In “Monkey News,” a builder complains when he discovers a chimp working at a new construction site, only to be told the chimp is a good worker.

Ricky and Stephen read passages from Karl's diary, which chronicles his daily observations, as well as profound thoughts. A fan letter asks the guys if they had any nicknames growing up; In "Monkey News": When one member of a bobsled team unexpectedly quits at the Winter Olympics, the team secretly replaces him with a monkey.

A fan letter asks Karl: If he were on a sinking ship, and could only save either Ricky or Stephen, who would he choose? Karl finds a news report that hedgehogs will be extinct by 2025. Also up for discussion: the story of a man who has a transplanted kidney from a woman and now claims he has an increased interest in housework. In "Monkey News": The owner of an airline reportedly hired a monkey to fly as co-pilot during a strike.

More e-mail questions for Karl, such as: If Karl could talk to any animal, which would it be and what would he say? Highlights from Karl's diary, including why he doesn't like meetings, and why he and his girlfriend always get in an argument after she gets a haircut. In "Monkey News": A story from the 1950s about a gangster who bought a racehorse. When none of the jockeys wanted to be involved with him, he got a monkey to race the horse.

Topics include: school curricula; physical altercations; human anatomy; whistling and happiness; birds and flight; Karl's thoughts on doppelgangers and the Big Bang; and the origins of the universe. Also: a "Monkey News" segment about eye surgery.

A fan letter asks Karl to reveal the most romantic thing he's done for his girlfriend on Valentine's Day. Another fan asks him to interpret Wittgenstein's statement "If a lion could talk, we could not understand him." From Karl's diary: He creates a jingle after giving a homeless man some change, and describes his trip to Malaga, Spain. In "Monkey News": Karl relates the story of Enos, a monkey who flew in the space shuttle in the 1960s.

Stephen asks Karl questions posed to guests on "Inside the Actors Studio, leading to a discussion of organ donation. From Karl's diary: A news report from India about an elephant who had a giant pair of slippers, and Karl's belief that scientists should give up trying to kill germs because it will only make them stronger and bigger.

Another question for Karl from "Inside the Actors Studio": "If heaven exists, what would you like to hear God say when you enter the pearly gates?" From Karl's diary: A news report that humans will have spoken to aliens by the year 2025 leads him to worry that aliens will try to read his mind, while a story about a baby who looked like a frog makes Karl think life would be more interesting if there were different types of humans. Plus, Karl's top five freaks.