October 1604. Plague has hit London, and the theatres are closed. But the capital's loss is Plymouth's gain, when a London theatre troupe, the Company, arrive on their 'Plague Tour'. Country physician Gabriel Taverner is bewitched and unnerved by the Company's sexually charged staging of OTHELLO. But when Gabriel's friend tells him of a dangerous, whispered conversation overheard during a brief break, he is relieved the Company will soon be on their way. Then one of the actors collapses, and Gabriel finds himself caught in a waking nightmare, where nothing is as it appears. Death is stalking the Company - but how can Gabriel hope to catch a cold-blooded killer, if he can't even trust the evidence of his own eyes?