Neil Patrick Harris attends the Elton John AIDS Foundation's 13th annual An Enduring Vision Benefit in New York
Neil Patrick Harris attends the Elton John AIDS Foundation's 13th annual An Enduring Vision Benefit in New York October 28, 2014. Reuters/Andrew Kelly

Neil Patrick Harris and his husband, David Burtka¸ are set to appear in FX's horror anthology series, "American Horror Story-Freak Show." Also, according to reports, Lily Rabe is returning to reprise her "American Horror Story-Asylum" role.

TV Line is reporting that Harris' character will appear in the last two episodes of "American Horror Story" Season 4. The report describes his character as a "chameleon salesman." Burkta's character will make an appearance in the final episode of the current series. The character will be seen with the fame-hungry Elsa Mars, played by Jessica Lange, in a "sexy storyline."

Meanwhile, Entertainment Weekly (EW) is reporting that Lily Rabe has signed on to once again play Sister Mary Eunice. This is the second time that the writers of "American Horror Story" are resurrecting a character from "Asylum" in "Freak Show." The microcephalic character Pepper, played by Naomi Grossman, of "Asylum" is part of Mars' freak show in the current season.

According to EW, Sister Eunice will appear in episode 10. The episode is likely to answer how Pepper ended up in Briarcliff Mental Institution. Rabe is expected to film her part this weekend. The actress, who has been part of all the previous three seasons, is doing a lead role in ABC's new show "The Whispers."

As previously reported, Matt Bomer, Neal Caffrey of "White Collar," is also guest-starring in "Freak Show." In episode 5, the actor will appear in a scene with veteran actor Michael Chiklis, who plays strong-man Dell, and Finn Wittrock, who plays the twisted Dandy. Bomer's first look has been released. [Check the First Look of Bomer's Character Here].

Speaking about episode 5, Ryan Murphy, co-creator of "American Horror Story," has said to The Hollywood Reporter that something "horrible and dastardly" happens in the episode. Also, he revealed that Bomer and Chiklis will appear in a seven-page scene, which is "really f----ed up." Murphy said that the scene is a "true horror scene," possibly the "most disturbing."

The episode 5 of "American Horror Story-Freak Show" is scheduled to air on Wednesday, Nov. 05.