Firstborn (1984)

A young divorced mother (Teri Garr) falls for an unstable drifter (Peter Weller). Her teenage son (Christopher Collet) and his kid brother (Corey Haim) see the boyfriend for what he is but their mother refuses to acknowledge that there's something off about him. Soon, the boyfriend becomes abusive and brings drugs into the house and things begin spiraling out of control. Directed by Michael Apted (COAL MINER'S DAUGHTER). What starts out as a drama about a divorcee dealing with loneliness and struggling to raise two boys by herself eventually turns into a dark ..... what? Thriller? Action movie? Whatever it is, it betrays its interesting promise and soon turns into a morass of banalities that we've been subjected to in countless other (and better) films. Some of the acting is good. Teri Garr brings a bruised pathos to her single mother and Peter Weller is suitably slimy. With two very young pre-stardom youngsters as Collet's classmates, Robert Downey Jr. and Sarah Jessica Parker.