Desperate Intruder

"Desperate Intruder" is an episode of Thunderbirds, a British Supermarionation television series created by Gerry and Sylvia Anderson and filmed by their production company AP Films (later Century 21 Productions) for ITC Entertainment. Written by Donald Robertson and directed by David Lane, it was first broadcast on 18 November 1965 on ATV Midlands as the eighth episode of Series One. In the official running order, it is the 17th episode.

Set in the 2060s, Thunderbirds follows the missions of International Rescue, a secret organisation which uses technologically-advanced rescue vehicles to save human life. 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. International Rescue's main antagonist is master criminal The Hood, who engineers or obstructs emergency situations for his own gain. In "Desperate Intruder", the organisation is forced into action to save two of its own members when Brains and Tin-Tin (voiced by David Graham and Christine Finn) are attacked by The Hood during an archaeological expedition in search of lost treasure.

In 1967, Century 21 released a condensed audio adaptation of "Desperate Intruder" on EP record (Brains and Tin-Tin, catalogue number MA 119), with narration by Christine Finn in character as Tin-Tin. The episode had its first UK‑wide network broadcast on 3 January 1992 on BBC2.