A conwoman sets out to swindle a day trader out of his millions, but when they’re both framed for his wife’s murder, they’ll have to come together to clear their names before they’re thrown in jail or wind up whacked by the day trader’s mobster father-in-law.

A conwoman conspires to swindle a wealthy daytrader by becoming his mistress. But when both?are framed for his wife's murder, she must prove his innocence and save his fortune to save herself.
(33 words)

Or some such. ?The story hook for me is the ironic reversal entailed in her objective goal. (I'm a sucker for dramatic irony.) ?She must switch roles, from exploiting him to rescuing?him. ?And she must save his fortune to save herself.

fwiw

A conwoman conspires to swindle a wealthy daytrader by becoming his mistress. But when both?are framed for his wife's murder, she must prove his innocence and save his fortune to save herself.
(33 words)

Or some such. ?The story hook for me is the ironic reversal entailed in her objective goal. (I'm a sucker for dramatic irony.) ?She must switch roles, from exploiting him to rescuing?him. ?And she must save his fortune to save herself.

fwiw

I ?kind of remember an old version of this logline, now it's much much better, very clear. I like it. I think that you can ?shorten it a little more.
When does the victim learn that the woman is a conartist? At the beginning or at the end? this can influence the writing. Anyway I think the movie can have many reveals (who killed the wife, maybe the trader? The trader is the real con artist, trying to put the blame on the con woman for an even bigger fraud and a murder?).
I suggest to change the end of the logline, "to clean their names" is vague, maybe they must find the real murderer before the police or the mobster father in love find them? I think that "come togher" is kind of implicit, you cna save a few words there.