The lead characters are ex-astronaut Jeff Tracy, founder of International Rescue, and his five adult sons, who pilot the organisation's primary vehicles: the Thunderbird machines.
In "The Man from MI.5", International Rescue field operative Lady Penelope is assigned to help British secret agent Bondson recover stolen plans for a nuclear device.
[3][4] On the French Riviera,[5] MI5 agent Bondson and his associate Tidman prepare to rendezvous with Captain Blacker aboard his yacht to take possession of some mysterious papers.
Bondson, who considers International Rescue ideally placed to help due to its advanced technology, explains that the papers are plans for a nuclear device that could threaten the safety of the world.
After the butler goes ashore to hit the Monte Carlo casinos, Carl, who has read about "Williams" in the news and intends to kill her, takes a boat out to FAB 2 and abducts Penelope to an empty boathouse.
Reaching the submarine just before the gang detonate the bomb, Gordon drills through the hull and floods the cabin with knockout gas, incapacitating Carl and his cronies.
[7] The model shots of the French coast incorporated a large background painting by special effects assistant Mike Trim which later appeared in "The Duchess Assignment" as well as episodes of Captain Scarlet and the Mysterons and Joe 90.
This was one of several scenes in Thunderbirds which used a subjective camera angle and forced perspective to realistically present live hands and the series' scale (1⁄3-lifesized) puppets in the same shot.
[13] Pointing out that "The Man from MI.5" was made shortly before the release of Thunderball, in which Bond tracks down a pair of atomic bombs stolen from a sunken military aircraft, McGown suggests that the episode's underwater action may have been influenced by the plot of the film.
He adds that through Bondson, "The Man from MI.5" is one of a number that "unashamedly capitalised on the Cold War cult of the secret agent whose skills defend the home from enemies unknown.
[12] A BBC review of the series soundtrack characterises the episode's music as "the spy theme James Bond never had – an urbane jazz fantasia, perfect for a mannequin about town".