Like most Hitchcock films, "Sabotage" is a great thriller directed with a fluid, self-assured style. But given its thriller genre what makes "Sabotage" unique is that moments into the movie we know the identity of the saboteur, we know who is the undercover detective, and we know that the police have all but solved the case. So Hitchcock's suspense must come from somewhere else and in the meantime he must entertain us with character development. And that task falls to his heroine. Hitchcock had an uncanny ability to cast actresses who were a perfect fit (at that exact point of their career) to play a particular heroine. Fortunately he again makes the right choice and we are treated to a fine performance from Sylvia Sidney (imagine an expressive Sasha Cohen without ice skates).

The film is essentially a Sylvia Sidney vehicle as she plays a woman who slowly realizes that her husband is a monster. She is a young American woman who married an older European (nationality unknown) man who apparently showed kindness to her and her young brother Stevie (played by Desmond Tester) when they were down on their luck. They moved to London to run the Bijou, a struggling movie house.

Among the notable scenes is the meeting between Sidney's husband (played by Oskar Homolka) and a spy contact at the London aquarium; to the backdrop of a huge turtle swimming in an illuminated tank. The tank cross-dissolves into Piccadilly Circus as it is demolished in his imagination.

Another is late in the film when Sidney sits in the theater in numb shock, watching a Disney cartoon ( ( "Who Killed Cock Robin ?" )). There is not a word of dialogue but her eyes and expressions subtly convey an emotional cavalcade of stunned realization, immense sadness, and barely suppressed hysteria that will stay in your memory forever. It is a rare example of the visual power of film and an illustration of what acting for the camera is all about.

And perhaps most amazing is the long and unbearably suspenseful journey of young brother Stevie across London, unaware that he's carrying a ticking time bomb.