Some Dean Koontz and Stephen King adaptations were pretty bad. Hideaway, Phantoms, The Dark Half, Sleepwalkers.

I really enjoy the movie Phantoms, but not because it's as good as the book. It's just a fun movie if you're into that genre. But we could definitely add almost every Stephen King adaptation to this list. Don't get me wrong--some of them I very much enjoy, but that doesn't mean they're not terrible (looking at you, The Stand (first one), Storm of the Century, and Tommyknockers).

Phantoms was by Dean Koontz.