Gothika (2003)

Because someone is dead doesn't mean they're gone.

After a car crash, criminal psychologist Dr. Miranda Grey regains consciousness only to find that she's a patient in the same mental institution that currently employs her. She's been accused of murdering her husband Dr. Douglas Grey —but she has no memory of committing the crime. As she tries to regain her memory and convince her co-worker, Dr. Pete Graham, of her innocence, a vengeful spirit uses her as an earthly pawn, which further convinces everyone of her guilt.