Babs pays Joyce Brewster, a long widowed mother wholly pre-occupied with checking up on her singleton son Andy (Rogen), a wannabe inventor whose life has long been bumping along the bottom.
He's come up with a an eco-friendly, coconut-based cleaning fluid that he hopes to flog to retail players such as Costco during a two-week marketing road trip across the States.
Just before he sets off his mother confesses that she had a fling with a young chap before she met his dad... whom Andy tracks down to San Francisco via the internet.
Reluctantly inviting her along for the ride, he secretly slots in a meeting with his mom and her old flame among his appointments with potential clients. What could possibly go wrong?