I have two swapped themed ideas.
One is where im holidaying in Vegas. I go wandering one night, befriend a prostitute, who unknown to me, is desperate to escape her life and pimp. She laces my drink, swaps clothes and bags with me, then flees the city in them, leaving me in her clothes, in the motel room to be found by him, where I would be made to take her place.
The second is where a woman is being forced to marry someone high up in the mob, but doesnt want to.She meets me in the bar of one of the hotels, invites me up to her room, then laces my drink and does the same as in my other idea.
I would look enough like her, or perhaps I look nothing like her, and the mob guy has me altered via surgery to look like her exact double.