Ka, the time-travelling cat, has disappeared, leaving just one clue - a word on Topher's computer screen: R*iche mou*nt.

When Topher discovers that 'Richemount' meant 'Richmond' in Tudor times, he fears that Ka is in terrible danger.

Cats were tortured in Tudor England, so Topher must try to find her before it is too late.

In doing so, he meets Queen Elizabeth and Doctor Dee, the court magician and astronomer, who thinks Ka can help him find the elusive philosopher's stone.

This is an exciting and transporting fantasy, exploring both contemporary and ancient issues.