When disaster hits the Titanic, the Doctor uncovers a threat to the whole human race. Battling alongside aliens, saboteurs, robot Angels and a new friend called Astrid, can he stop the Christmas inferno?

• BBC Cymru Wales
• David Tennant
• Kylie Minogue
• Russell Tovey
• Jimmy Vee
• Clive Swift
• George Costigan
• Geoffrey Palmer
• Gray O'Brien