Seth (Spooks)

Morton Chapel’s daughter Megan has come out of catatonia at last, but she didn’t come back to life alone. Seth, her demonic alter ego, is with her, and the two of them have already wreaked bloody havoc. The hunt is now on between Chapel, who’s convinced killing his daughter is the only solution, his team bent on preventing him from doing so, and Megan’s grandfather, an insane, megalomaniac industrialist who believes he owes Seth his fortune...