When British Intelligence, following a series of experiments designed to increase alertness of long-distance lorry drivers through use of tonal repetition, discovers chordation that completely erases all memory, it is obvious that such a cleansed mind may be programmed to perform any type of action. Erstwhile agent Peter Clarke (John Waters), inactive for years but tethered to the Agency's knowledge of Clarke's direct involvement in a homicide, is chosen as courier to transport an audio tape of the tones to his native Australia, his Agency controller, Ainsley (Vincent Ball), hoping that a representative from the "other side", one Korchek (Keith Lee) will follow Peter, find an opportunity to seize the tape, and subsequently neutralize himself through listening to it. This somewhat Byzantine contrivance is further complicated when a third set of individuals (never identified) becomes engaged in the affair and a viewer gradually comes to have an unquiet sense that none of the principals may with assurance be what is at first seemed, and this disconcertion is maintained until the unexpected climax. The film, following some early stock footage of London, is set and shot in Sydney, the mean streets of which become an unfortunate venue for Clarke when, after the fashion of 1940s era private eyes, he is continually being attacked, battered, shot, et alia, until one wonders at his durability. Acting laurels must go to Ball for his polished turn as a senior operative in this opaque tale that is impaired in spite of able direction and editing by overmuch post-production cutting.
