Drowning Mona (2000)
Drowning Mona is a 2000 comedy-mystery film starring Danny DeVito as Wyatt Rash, a local police chief from Verplanck, New York, who investigates the mysterious death of Mona Dearly, a spiteful, loud-mouthed, cruel and highly unpopular woman, who drove her son's car off a cliff and drowned in a river.
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