博士的塔迪斯被追尾，肇事船居然是泰坦尼克号。原来一家外星旅游公司仿照泰坦尼克号制造了一艘巨大的泰坦尼克号宇宙飞船。但是飞船却连续遭遇不幸：防护罩被毁，装上陨石群，船长死去，服务机器人嗜杀成性……。...

A meeting in a London bus with jewel thief Lady Christina takes a turn for the worst for the Doctor when the bus takes a detour to a desert-like planet, where the deadly Swarm awaits....