October, 1930. His Majesty's Airship, the R101, sets off on her maiden voyage to the farthest-flung reaches of the British Empire, carrying the brightest lights of the Imperial fleet. Carrying the hopes and dreams of a breathless nation. Not to mention a ruthless spy with a top-secret mission, a mysterious passenger who appears nowhere on the crew list, a would-be adventuress destined for the Singapore Hilton... and a Time Lord from the planet Gallifrey. The future of the galaxy will be hanging by a thread.