This is a quite effective thriller. The filmmakers slowly raise the level of tension as the heroine realizes that she is at the center of a sinister plot.
There is something satisfying about watching Audrey Hepburn find her inner strength and intelligence to save herself and foil the villains' machinations. Hepburn is aided by her costars as well. The men playing the villains (Alan Arkin, Richard Crenna, and Jack Weston) are convincing and really fun to watch, and Julie Herrod is great as an awkward 12-year-old girl who helps Hepburn turn the tables on her antagonists.