Actor Aidan Gillen had akey role on one of the most important television series of all time—Game of Thrones. Now he's on a new show, Project Blue Book. Gillen stars on the series as Dr.

The series, starring Aidan Gillen and Michael Malarkey, will air its season one finale on Feb. 26. 'Game of Thrones' standout Aidan Gillen, to-die-for costumes and UFOs -- what's not to love?

Murray/Getty/Alishia Love EXCLUSIVE: Aidan Gillen (Game of Thrones), Joe Alwyn (The Brutalist), Naledi Murray (Sweet Tooth), Ben Chaplin (September 5) and Sebastian Orozco (The Crow) round out the ...