The CW announces premiere dates for <i>Vampire Diaries, Supernatural, Smallville</i> The CW announced a Sept. 10 premiere date for its new teen vamp series The Vampire Diaries, which will air at 8 p.m. ET/PT, followed by the season premiere of Supernatural at 9 p.m. The shows make up the network's new Thursday-night lineup. Smallville moves to its new Friday 8 p.m. timeslot on Sept. 25.