Thunderbirds Are Go - Season 1 Episode 8

A series of cascading equipment failures leads John to realise that rogue A.I. has gained control of Thunderbird 5. The programme is sending false monitor images to Tracy Island to deceive the other brothers. John finally gets through to Lady Penelope and informs her of the situation. Once the other brothers figure out what is going on, Alan is despatched in Thunderbird 3 to rescue John.