On
Tracy Island,
Christmas has arrived and the area surrounding the Tracy villa is miraculously covered in snow. As well as
Lady Penelope, International Rescue are hosting a special guest for the holiday – a young boy called Nicky.
Jeff, dressed as
Santa Claus, recalls the events that led up to this day. At Coralville Children's Hospital, which is looking for ways to raise money to build a new solar therapy wing. In collaboration with rocket manufacturer Saunders Automations and Harman's department store of New York, the hospital board devises a Christmas
publicity stunt to benefit all involved: a Saunders rocket, loaded with Harman's toys and launched from the store's roof, which will overfly Coralville and parachute-drop its cargo into the hospital car park – thus providing a Christmas present for every Coralville child. Instead of a toy, one of the children will win a very special prize: Christmas Day on Tracy Island. On
Christmas Eve, shortly before the rocket launch, criminals Scobie and Straker break into the deserted Harman's. Using drills to remove a portion of wall, they penetrate the property next door – the high-security vault of the
Second National Bank – and set about stealing $10 million in
gold bullion. To avoid touching the vault's alarmed floor, they shoot a cable into the opposite wall and use it like a
Tyrolean traverse, Straker holding the line taut while Scobie, suspended from a harness, loads the gold into a sack. As they prepare to escape with their loot, they accidentally knock a pencil to the floor, setting off the alarm. To evade security guards, they lock themselves in what turns out to be the rocket's cargo compartment, which is being transferred to the launch pad in a freight elevator. By the time Scobie and Straker's pursuers realise where they have hidden, it is too late to stop the launch, and the rocket blasts off with the robbers trapped inside. After the rocket drops its cargo over Coralville, the hospital staff open the compartment to find Scobie and Straker amid the gold and boxes of presents, having been knocked out by the
g-forces. The hospital hands the robbers and gold over to the police and receives enough reward money to fund its new wing. Having flown out in
Thunderbird 2,
Virgil collects Nicky, the prize winner, and flies him to Tracy Island to spend Christmas with International Rescue. In the episode's subplot, festive preparations on Tracy Island are under way when
Brains hears Virgil expressing regret that the chances of a
white Christmas in the
South Pacific are extremely low. Brains has an idea and secretly builds a machine in the roof of the Tracy villa. In the closing scene, set after Nicky's arrival, Brains asks everyone to shut their eyes and then activates the machine: a
snow-making system. Opening their eyes, Nicky and the International Rescue team are delighted to find the villa and its surroundings under a blanket of snow. ==Regular voice cast==