Basic Instinct (1992)

Continuity mistake: During the interrogation scene, Stone has her legs crossed right over the left then suddenly left over the right and a second later (during the shot where she wears no underwear) right to left again.

Gus: I thought you said he was a rock and roll star.
Lt. Walker: He was a retired rock and roll star.
Capt. Talcott: A civic-minded, very respectable rock and roll star.
Gus: What's that over there?
Nick: It looks like some civic-minded, very respectable cocaine to me, Gus.

Trivia: Director Paul Verhoeven actually has a PhD in mathematics. He received it back in the 1960's in Holland. He left the field and became a film director. (From Director's commentary on "Basic Instinct: The Original Director's Cut".).

Question: Did Stone have a motive for all that she did or was she nuts and doing it all for fun?