Dr. Jessica delivers surprising news to the emotionally invested couples as the experiment nears the halfway point.

Emotions run high as the couples cope with seeing footage of their real spouses with their experimental partners; the experimental couples are tasked to become more vulnerable with one another, but not everyone is ready to open up.

The couples encounter the biggest challenge yet as the experiment nears its end.

The experiment is coming to a close but before the couples are sent home, they're faced with their biggest challenge yet--meeting their experimental spouses' real spouse. Not everyone is happy by what they learn and some begin to have serious regrets

Now that the experiment is almost half way through, the experts visit all of the experimental couples in order to check in and deliver some surprising news.

Two weeks have passed since the married couples have reunited, and now they're challenged with the decision of whether they've made the right choice with their spouse, or whether it's time to part ways forever.

The experimental couples are getting to know each other in a brand new living situation. By the end of the day, boundaries are tested as the couples re-discover what it’s like to build a connection and attempt to navigate their initial attractions.

During the first week of the experiment, the couples explore each other's passions, personalities and patience.

The experimental couples reflect on their time together. As the couples prepare to say goodbye, letting go of their “new life” proves difficult for some.

With the switch almost halfway over, the experimental couples participate in an exercise to help build emotional intimacy, with some continuing to open up and others beginning to shut down; the experts check in and deliver a surprising announcement.

As switch therapy begins to wind down, the experimental couples learn how to rely on a spouse in order to navigate the unexpected; the couples get a new perspective on their time in the switch at intense group summits.

The couples reunite and must choose between parting ways or recommitting to their marriages.

Four married couples are introduced as they embark on an emotionally difficult journey to help repair their relationships. Viewers learn each of their love stories--how they met, how they fell in love, how their marriages took a turn for the worst and why they are willing to risk everything in order to save it.

The experimental couples confront their biggest challenge yet, as they come face-to-face with their experimental spouses' real spouse; not everyone likes what they learn, and feelings of jealousy and regret begin to surface for some.