It all began with a night at the theatre. The nation’s most famous psychologist Dr Ophelia Hart had been receiving death threats through the post. There was nothing unusual in that as Ophelia had made many enemies during her career as a highly sceptical investigator of the paranormal. It wasn’t that she was closed-minded. More that no case she’d ever come across could convince her there was any truth to the paranormal. 

She always began her investigations open to being proved wrong. And now a case had come along that might just force her to change her mind.

A mystic from the east had recently arrived in Britain. The mystic was a showman and the darling of the press. Here was no ordinary conjurer, as the audiences of his sell out shows would soon discover. Even the Royal Society and the Magic Circle admitted to being baffled by the tricks he performed.

 Ophelia received an unsigned letter warning her not to attend the mystic's final London show. Undeterred she purchased tickets for the event and invited the Doctor to accompany her.

The Doctor was her newest friend and a fellow scientist. And he was more than happy to accept her invitation as he’d like to see this mysterious ‘Illusionist’ before the Brigadier and UNIT got in on the act.

Unknown to her his Tardis had detected a spatial-temporal anomaly. Its locus: the Wimbledon Theatre, London, 198-