Mercury Falling is the fourth episode of Gerry Anderson's New Captain Scarlet.


Captain Blue and Destiny Angel pilot the International Space Agency shuttle Mercury on a top secret mission into space; they are to deploy a new satellite into Earth orbit, which will provide early warning of an imminent attack by identifying Mysteron energy on Mars. However, just as Mercury achieves orbit the shuttles controls are taken over by an outside force, and its systems lock onto a new flight path; Spectrum then receives a transmission from an unidentified extortionist who demands a ransom of $50 million in diamonds or else they will initiate Mercurys re-entry over North America and crash the shuttle onto Washington DC. Captain Scarlet heads for the launch facility to investigate, but when he arrives he learns from Doctor Celine Kopalski that Captain Black is already on the base; Scarlet tracks down the Mysteron agent, but Black evades capture and makes off in Scarlets Cheetah RRV; with Scarlet in pursuit in a helicopter, a high-speed chase ensues, ending when Harmony Angel arrives in an Interceptor and blows up the RRV, apparently destroying Black. Back on the shuttle, Blue and Destiny are informed that the U.S. Government has agreed to meet the ransom demands, and that Kopalski has been chosen to deliver the diamonds to a drop-point in an old abandoned mining town named Prosperity. However, Kopalski is actually the saboteur, and she switches the briefcases and steals the diamonds. But when she returns home with her ill-gotten gains she meets Captain Black, who hypnotises her into revealing the location of the laptop that is controlling the shuttles systems. Black obtains the device and uses it to set Mercury on a collision course with the White House…