An air-liner arriving in London from Rome is not thirty minutes early, as the pilot assumes, but in fact six days late. None of the crew or passengers - who have a mysterious bruise on their arms - can account for the missing six days, no extra fuel has been used and the plane has not been tampered with in anyway. An Eastern bloc pilot is among the names on the passenger list but he is killed before he can be interviewed, and he is not the only casualty. As Sir Curtis was on board the plane Department 'S' has an interest in investigating what happened.
—don @ minifie-1