American Horror Story, an anthology series that debuted on FX in 2011 and in which each season covers a different theme from the world of horror.

American Horror Story has built its own unified universe through connections between characters and events from different seasons, and it all began with Murder House. Season 1 was all about a haunted house where the ghosts of its former residents and their victims lived, and where the strangest things happened all the time. Murder House introduced the audience to the tone and style of American Horror Story as well as to some of its frequent collaborators, such as Evan Peters, Denis O’Hare, Jessica Lange, and Sarah Paulson. Many of them returned in subsequent seasons, and there’s one actor that made his debut in season 4, titled Freak Show, but could have ed in season 1: Neil Patrick Harris.

Related: American Horror Story Murder House: The True Story That Inspired Season 1

The mansion in Murder House had a lot of ghosts, most notably Moira O’Hara (s Conroy and Alexandra Breckenridge) and Tate Langdon (Peters), but there were also Chad and Patrick, a gay couple that moved into the house before the Harmons. Chad and Patrick restored the house with the intention of selling it, but when the economy and house industry collapsed, they found themselves unable to sell it and move out. Their relationship soon began to crumble as well, with Patrick cheating on Chad, which led to a big fight between them, after which Tate, dressed in the BDSM rubber suit Chad had bought, killed him and later Patrick, and arranged the scene to make it look like a murder-suicide. Chad was played by Zachary Quinto and Patrick by Teddy Sears, but the pair could have been played by a real-life couple, as Neil Patrick Harris and David Burtka were offered the roles, but turned them down.

American Horror Story Freak Show Chester Creb

In an interview with Neil Patrick Harris revealed that he and his husband turned down an offer to appear in the first season of American Horror Story, and they would have played Chad and Patrick. Harris explained that they had “relatively recently” appeared in the comedy movie A Very Harold & Kumar 3D Christmas, where David played his “drug dealer” and they had been pretending to be in a relationship as Harris’ character was straight, so their relationship was, in his own words, terrible. After that, they were offered the roles of Chad and Patrick in American Horror Story, which meant playing a toxic couple once again, though this time their characters were murdered and became ghosts. Harris added that he loved the idea of the show but they had just played themselves as a couple that didn’t get along, and doing it again felt weird.

Harris also said that Burtka wanted to American Horror Story season 1, but he insisted that he didn’t want them to be known “as a couple that don’t like each other”. Neil Patrick Harris ended up ing American Horror Story in season 4, Freak Show, where he played Chester Creb, a deeply disturbed salesman, magician, and ventriloquist who briefly owned Fräulein Elsa’s Cabinet of Curiosities and killed Maggie (Emma Roberts) during a trick with the magic box. It’s hard to say if appearing in Murder House would have brought Neil Patrick Harris back for subsequent seasons, but at least he got to this universe a couple of seasons later.

Next: American Horror Story: How Every Murder House Character Died