I Am the Other Woman (2006)

Unsuspecting Robert Fabry (August Diehl) checks into a Frankfurt hotel on business and is soon involved in an incident with a slutty, drunken woman (Katja Riemann) dressed in a revealing bright red dress. When she causes a ruckus in the lobby, he comes to her rescue; soon, she is in his hotel room - and his bed. The next morning, she has disappeared. When Robert arrives for his appointment at a law firm, he is introduced to the prim Carolin Winter. Despite the complete contrast in her appearance, he recognizes her as the woman with whom he spent the night. Carolin, on the other hand, has no memory of their encounter! Perplexed but smitten, Robert finds himself madly in love with a woman living a double life.

Carolin introduces him to her family. Her wheelchair-bound father is a stern, domineering patriarch who exerts a powerful influence over his daughter. The rest of the bizarre ménage consists of her doting and passive mother, a male servant and an attractive, stiletto-wearing, enigmatic woman.

What follows is a spellbinding story of a man determined to get to the bottom of the mystery presented by his new lover. He is soon embroiled in a domestic drama that has as many twists and turns as Carolin's ever-changing personality. I Am the Other Woman plays out as a haunting and intriguing family romance, while also resonating with meaning for those alert to the role played by a manipulative autocrat (Armin Mueller-Stahl).