Television writer Jeff Brooks, vacationing on a world cruise with his wife, Sandy, finds himself in a cabin next door to muscleman actor King Banner and his wife, Claire. Sandy has been unable to become pregnant because Jeff is too nervous and tense. Hoping that a restful trip will solve the problem, Jeff consults the ship's doctor, who gives him aspirin in the guise of a fertility pill. The couples' frequent drinking parties and trips to each others' cabins create confusion when Sandy and Claire both become pregnant. Jeff remains in a state of drunkenness because he recalls seeing Sandy, clad only in a revealing negligee, entertaining King; in addition, he remembers awakening one morning to the sight of Claire passed out in the same room. Some questions about the babies' parentage obviously remain to be answered.