You Never Can Tell is a charming light comedy set in an English seaside town. Famed authoress, Mrs. Clandon, and her three children, Dolly, Phillip and Gloria, have returned to England after eighteen-years in Madeira. The children have no idea who their father is and, without realizing, invite him to a family lunch. Mr Valentine, the determined dentist, has become besotted by Gloria, who considers herself a modern woman with no interest in love or marriage. The play races along as a comedy of errors and confused identities, with the friendly and wise hotel waiter offering his insightful phrase "...you never can tell."