Black Widow(2007)

Peyton is a 20-year-old gold digger and drifter who meets Charles, an older man of wealth and status. After seducing him into marrying her, she deviously begins putting her plan into action. As the picture perfect wife, she gives him everything a man could ask for: allowing him to have sex with other women and performing for him with other men. But as their three-year anniversary nears, it's time for her dreams to come true, to become a Black Widow. Peyton begins to slowly poison Charles, but he has a plan of his own.