In Singapore, a private detective and the British authorities are on the trail of a crime syndicate that kidnaps a nuclear physicist with the aim of selling him to the highest bidder.

Someone is murdering the cast and crew of a new Hollywood movie, and the leading lady may be next. As a police detective locks down the lot and refuses to let anyone leave, the studio’s publicity head and his secretary attempt to solve the murders themselves.

After Jim Barston is mysteriously killed in Australia, his wife, Helen, lays claim to the estate of Gerald Mortimer Barston in England, asserting that her husband was the missing son and heir. In reality, Jim was the cousin of the true heir, who is also named Jim Barston. Despite having no legal proof, Helen convinces the trustees to accept her claim and is installed as mistress of the manor. Jim Barston appears and proves his identity, although Helen initially believes him to be an impostor.

Angela and Bob Brooks are an upper-class couple. Unfortunately, Bob is an unfaithful husband, but Angela has a plan to win back her husband's affections.

Walter Mitty, a daydreaming writer with an overprotective mother, likes to imagine that he is a hero who experiences fantastic adventures. His dream becomes reality when he accidentally meets a mysterious woman who hands him a little black book. According to her, it contains the locations of the Dutch crown jewels hidden since World War II. Soon, Mitty finds himself in the middle of a confusing conspiracy, where he has difficulty differentiating between fact and fiction.

Amanda and Elyot are one another's former spouse. Elyot is remarried to Sibyl and Amanda married Victor. Unexpectedly, both honeymooning couples arrive at a hotel on the same day and are put in rooms with adjoining terraces. Things go well until Amanda sees Elyot on the adjacent terrace.