A woman (Jean Simmons) and her brother (David Tomlinson) travel to Paris for the 1889 World Fair, but he disappears after their first night and all the hotel staff deny his existence. This is a well written, produced and acted mystery/suspense film as an innocent woman abroad becomes increasingly distressed over the disappearance of her brother until a handsome artist (Dirk Bogarde) starts to help her. Jean Simmons gives a wonderful performance in the lead role and is well supported by the rest of the cast. The script weaves the suspense against a background of Parisian night life, some danger and a hint of romance. Unusually for the period the film was made a number of the scenes have the French characters speaking French.