In this taut, twist-filled thriller, Robert Elliot is a renowned American economist who stands on the verge of a government advisory role, yet privately he runs a London-based business espionage ring. His carefully chosen four operatives are the corrupt Foreign Office official Alex Hellman, the masseur Bert Parsons, the sex worker Christina Larsson, and the scientist David Baker. As the stakes rise, Elliot schemes to silence any potential leaks by orchestrating a deadly, self-serving gambit: have his associates kill each other on the same fateful night, ensuring that no one outside the circle can implicate him.
On the night of the massacre, Elliot keeps a ruthless tally by listening for a string of phone rings, a quiet, eerie metronome that marks each operative’s location. The plan unfolds in carefully choreographed steps. First, [David] leaves for [Alex]'s apartment and tamperingly replaces the diabetic official’s insulin with a lethal dose. Although delayed, David returns home only to fall prey to his own sonic weapon—a device he had once demonstrated to Elliot and which Christina had cunningly planted on a timer, ready to claim him when the time came. In a parallel thread, Christina returns to her own apartment, where Bert arrives with a key handed to him by Elliot, and Bert murders Christina in the shower. To muddy the forensic waters, Elliot has already had a fragment of skin removed from a corpse placed beneath Christina’s fingernails, a cruel ruse aimed at deceiving pathologists.
Meanwhile, Alex retrieves a stash of tools from a locker at London Marylebone station, including a hammer, and lies in wait outside the massage parlor where Bert works. He phones Elliot, confessing his hesitation and his plan to back out, but Elliot’s threats drive him to go through with the deed. The attempted paradox of loyalty and fear culminates when Bert is fatally struck with the hammer in the back passage. Alex, panicked by what he has done, returns home without signaling Elliot that the mission has progressed, and Elliot then travels to confront him at his residence. After confirming the murder, Alex collapses and dies—his insulin dose proving lethal.
The following day, Elliot, about to depart for Washington, D.C., receives a final payload: a special-delivery package that contains a notebook written by David. The notebook’s pages are saturated with a deadly poison that can be absorbed through the skin, a grim device designed to ensure Elliot’s demise should he ever suspect the truth. As Elliot is driven toward the airport, he opens the deadly package and reads a confession that circularly indicts him—David never fully trusted Elliot and, in the event of any hint of Elliot’s fall, would presume him responsible. The poison takes effect in minutes, and Elliot collapses at the gates, dying before he can begin his new post.
The film’s web of manipulation, secrecy, and lethal misdirection leaves viewers with a chilling meditation on how power can seed destruction from within. The intersecting betrayals disturb the balance Elliot sought to protect, revealing a masterplan that backfires in the most final way possible. Throughout, the atmosphere remains cool, controlled, and relentlessly suspenseful, with each staged murder functionally mirroring Elliot’s cold calculation: nothing is accidental, and every action is a step toward an irreversible end.
