Continuity mistake: In the first scene of the movie Sharon Stone ties Jonny Boz's right hand with her white silk scarf. When we first see his hand it's wide open than in the next shot it's closed only to open as she pulls the knot tightly. (00:03:35)
Continuity mistake: When Michael Douglas walks into Jeanne Tripplehorn's apartment we see a chair on the left of the screen. Later in the scene the chair is pushed right up against the table, which it wasn't in the previous shot. (00:35:30)
Factual error: The light reflections at Tremell's beach house are not the ones an ocean would make. The reflections are from large flat areas of almost calm water - like in basins - but there are none around.
Character mistake: When Beth encounters Nick after Gus has been murdered, she puts her hand in her pocket and steps forward, prompting Nick to order her to freeze and to take her hand out of her pocket while aiming his gun at her. However, she just keeps reaching for what's in her pocket and approaching Nick, resulting in him shooting her. Considering that she works on the police force, she absolutely should have known for a fact that she was being suspected of reaching for a gun, but thinks nothing of it.
Other mistake: Beth gives Nick his keys, saying he left his keys at her place, meaning they're his keys, but then she takes them with her, and those were the same keys she had in her pocket when she was shot.
Factual error: When Nick is looking up information about Hazel, the computer says she was released from San Quentin. That's a men's only prison.
Character mistake: When we see the door to Elisabeth's, her name is spelled with a s. Later when Nick looks her up on the computer, it's spelled Elizabeth.
Continuity mistake: At the beach house, Catherine is cutting up a large piece of ice with an ice pick. Depending on the direction of the camera, the ice changes size: in one shot it's all together; but in the next shot there's a large chunk pushed to the left of her.
Continuity mistake: Michael Douglas waits in the dark in Jeanne Tripplehorn's apartment and says to her after she walks in, " Tell me about Catherine". At first we see a couch and chair on the right side of the room but two shots later as he walks towards her these two items have been removed from the room. (01:38:40)
Continuity mistake: During the first sex scene between Michael Douglas and Sharon Stone, Miss Stone's nipples at first are very erect, but in the next shot are not.
Revealing mistake: When Jeanne Tripplehorn meets with Michael Douglas it's obvious by the flat reflection of the studio lights that she's wearing prop glasses. (00:13:45)
Continuity mistake: When Nick and Gus are driving Katherine to the police station for the first time, they drive past the same stretch of coast about three times throughout the scene. Most obviously seen by the position of the small island - it jumps from being in the distance, to being even with the car, then behind the car, then in front again etc.
Answer: She is portrayed as a psychopath with an uncontrollable urge to kill.
raywest ★
I wouldn't say that she had an "urge" to kill. Rather, she was willing to "dispose" of people by killing them. She would kill people who were in her way or were no longer interesting/useful.