Egypt, 1922
The Doctor and Clara are on a Nile cruise after their exhausting Christmas escapade.
Among the passengers is celebrated illusionist, Harry Houdini, who regales his fellow travellers with a magic show. The unimpressed Doctor tries to spoil it for Clara by telling her how each illusion is performed. But Clara is intrigued with the handsome Hungarian-American.
When they disembark at Giza, a huge crowd has gathered. They've come to witness Houdini's most sensational escape act yet: He is to be bound, mummified, sealed in a stone sarcophagus and buried under the Pyramid of Cheops.
Only the Doctor knows that this will incur the wrath of the powerful Osirians (an alien race who were basis of the ancient Egyptian deities and who built the Pyramids for space and time travel) but his attempt to stop Houdini results in his arrest....
Thats all I know so far.