Haynes is set to appear in a Season 2 episode of the horror-dramedy as a mysterious patient, EW.com reports. Scream Queens returns Tuesday, Sept. 20 at 9/8c, with John Stamos (Full House) and Taylor Lautner (Twilight) now part of the ensemble, as doctors in the new hospital setting.
Haynes of course wrapped up a “trial run” as an Arrow series regular (playing Roy Harper aka Arsenal) in April 2015, and has made one encore since, midway through Season 4.
“I asked to step away [from Arrow] because I cared more about my mental and physical health than my career at the time,” he explained to Entertainment Weekly. “I’ve had terminal anxiety my entire life. Physically ill, fainting. I’m 27 years old, and I have an ulcer. I had to step back.”