Unbreakable Kimmy Schmidt Season 1 available March 6 on Netflix.

Before being picked up by Netflix, Unbreakable Kimmy Schmidt was produced for NBC, and it features some of the formulaic rhythms and humor of a network sitcom. But it’s also odder and darker than typical network fare, and it probably would have gotten lost had it stayed on NBC. Instead it’s being allowed to flourish on Netflix (which has already ordered a second season unencumbered by broadcast limitations), and the first six episodes indicate a show that has some serious weirdness lurking underneath its sunny sitcom exterior.

Like Fox’s recent The Last Man on Earth, Unbreakable starts with a pretty grim premise: The title character (The Office’s Ellie Kemper) is one of four women rescued from an underground bunker in Indiana, where they’d been held captive for 15 years by a deranged cult leader, who told them that the world outside had been destroyed. Cut off from the world for half her life, Kimmy emerges determined to make something of herself, and she moves to New York City for a fresh start.

The contrast between Kimmy’s unbreakable optimism and the harsh cruelty of the real world provides the show’s biggest laughs, and Kemper is great at playing a character whose naïveté hides serious internal trauma (as she did on The Office). Co-created by Tina Fey and fellow 30 Rock writer/producer Robert Carlock, Unbreakable is mostly about the absurdities Kimmy encounters as she attempts to rebuild her life, including her flamboyant, forever-aspiring actor roommate (Tituss Burgess), her nutso landlady (Carol Kane) and her employer, a self-absorbed trophy wife (Jane Krakowski, essentially reprising her 30 Rock role as self-absorbed actress Jenna Maroney). There are plenty of typical sitcom misunderstandings and miscommunications, and some of the humor is disappointingly tame coming from Fey and Carlock.

But the looming darkness is what makes Unbreakable worth watching, whether it’s Kimmy dealing with severe PTSD or conceding that there was “weird sex stuff” going on in the bunker. Regular daily life can be just as disturbing and surreal as being trapped in a doomsday cult, and at its best, Unbreakable understands that the best way to deal with that is to laugh at it.