Chapman, now engaged to marry a man and living a preppy life in Brooklyn, New York, is sentenced to 15 months in prison. She is sent to the same facility where Alex is doing time.
Orange Is the New Black not only shows Chapman's fish-out-of-water experience in prison, but also the social dichotomies and hierarchy among women. It's based on a memoir with the same name by Piper Kerman, who spent one year in a women's correctional facility.
The series has already been given a second season.
"Anyone that sees the show they're like, 'Oh, there's nothing like this on TV'. Which there isn't and that's really cool," Prepon, 33-year-old, says.
She says the rawness of the series also makes it special.
Creator Jenji Kohan "wanted it to be as raw and real as possible", she says. "We wear, like, literally the federal prison-issue wardrobe, even down to the bras without underwire because you can't have underwire in prison. We're not allowed to wear a lot of makeup. ... There's a storyline where I actually barter to get black eyeliner, so every inmate has their own kind of thing that individualises them."
Because the show is about a women's prison, Prepon is largely surrounded by women on the set.
"I grew up with guys. I'm not used to hanging out with a bunch of chicks," she laughs. "My friends were like, 'What are you gonna do with all those women around?' But they're amazing. There's not one diva. Everyone is so cool."
Prepon was a member of the cast of the long-running sitcom That '70s Show which also starred Topher Grace, Ashton Kutcher, Danny Masterson, Mila Kunis and Wilmer Valderrama. They have all continued to work since the show went off the air in 2006.
"It's kind of rare that everybody on a cast moves on to awesome stuff. We're really fortunate and we all kind of keep each other in check. Like Danny [Masterson], I dated his brother for nine years. I'm like best friends with his mom, so Danny really is like my brother. It's a really tight group, it's great."
TV profile
Who: Laura Prepon, former That '70s Show regular
What: Orange is the New Black
Where and when: TV2, 11.30pm
- AP