Dr. Tess Coleman (Jamie Lee Curtis) and her fifteen-year-old daughter, Anna (Lindsay Lohan), are not getting along. They don't see eye-to-eye on clothes, hair, music, and certainly not in each other's taste in men. One Thursday evening, their disagreements reach a fever pitch - Anna is incensed that her mother doesn't support her musical aspirations and Tess, a widow about to remarry, can't see why Anna won't give her fiance (Mark Harmon) a break. Everything soon changes when two identical Chinese fortune cookies cause a little mystic mayhem. The next morning, their Friday gets freaky when Tess and Anna find themselves inside the wrong bodies. As they literally walk a mile in each other's shoes, they gain a little newfound respect for the other's point of view. But with Tess's wedding coming on Saturday, the two have to find a way to switch back - and fast.