tunnel in case of a water leak. Steyner soon finds out that Slater is having an affair with his wife, but allows it to continue because it will keep Slater away from the mine, so that the safety charge can be disabled without his knowledge. Meanwhile, syndicate head Farrell has a German member of the syndicate and his young family assassinated by bomb (in a Christmas gift box) after German stock-exchange difficulties hurt Sonderditch interests. While Slater and Terry are holidaying together over a warm Christmas, the final breach is made in the dike and a wall of water roars into the mazes of tunnels and shafts. The mine begins to flood, trapping a thousand workers. Slater hears of the disaster on the radio news, and flies with Terry in her small private plane back to the mine, making a hair-raising emergency landing on the access road. Slater and Big King descend into the mine, amidst rising flood waters, to repair and reconnect the electrical line to the explosive safety charge that will seal the dike hole. They succeed, but only because Big King sacrifices his own life to detonate the charge, letting Slater fall injured into a rubber dinghy in the flooded tunnel and escape. Meanwhile, Steyner is murdered by Marais, one of his accomplices, running him down with his Rolls-Royce limousine while they observe the mine rescue operations from a nearby towering rubble/slag hill after they hear radio reports of Slater's explosive charge sealing the dike and saving the mine, confirming that their plan has unraveled. Marais then goes over the steep hill's edge after hitting his boss, dying as the car crashes and explodes. This conveniently leaves Terry free to continue her relationship with Slater, as her grandfather tells him again as he is loaded into an ambulance – "Slater, you're a maniac!” - with a satisfied smile, and Terry tells Slater, "I love you", as the film ends. Cast Roger Moore ... Rodney "Rod" Slater Susannah York ... Terry Steyner Ray Milland ... Hurry Hirschfeld Bradford Dillman ... Manfred Steyner John Gielgud ... Farrell – syndicate head Tony Beckley ... Stephen Marais Simon Sabela ... 'Big King' Bernard Horsfall ... Dave Kowalski Marc Smith ... Tex Kiernan John Hussey ... Plummer Bill Brewer ... Aristide George Jackson ... Mine Doctor Ken Hare ... Jackson Ralph Loubser ... Mine Captain Patsy Kensit ... Daughter of German syndicate