Help me find the name of an old movie, description below

The main character is a police officer who, along with her partner, investigates strange incidents and rides together in a police car. During the investigation, her partner goes missing. The police officer follows her partner's trail and descends underground into a cave. There, she encounters an elderly couple—a creepy old man and woman who act like caring owners of a lair. The old man and woman claim to be husband and wife, but during their conversation, it becomes clear this is a lie. They are not human, but minions (or puppets) of an alien intelligence, masquerading as the elderly couple. They lure the police officer into a trap, paralyze her, and hand her over to the alien creature. The aliens amputate all of her limbs (arms and legs).