A Bird in the Bush (2008)

Out-of-work college professor Grant Oldman gets more than he bargains for when he brings an unknown woman to pose as his wife for a dinner party. After a disastrous evening, Grant finds himself homeless and unemployed with the unwanted task of supervising his unstable date that has inadvertently kidnapped the key witness to a fatal mob massacre. With federal agents hot on their trail, they must escort the witness to safety and escape the city before the mafia can execute its deadly plans.