The three Nemesis agents recover from a plane crash in the Tibetan mountains to find their injuries healed. In the course of the episode, they learn they have had new abilities bestowed on them by their rescuers, people from an ancient civilisation, and have to evade capture from the Chinese military.

The agents are sent to the Caribbean to investigate a newspaper advert asking for "a parrot that speaks Greek", which Tremayne has worked out is a signal for participants in an undercover operation.