In the middle of performing an operation on a British public servant, the surgeon is secretly replaced by an unknown man, who finishes the operation... When this is discovered, the initial suspicion is that the 'replacement' botched it up on purpose - however, it turns out he performed it flawlessly. So why was the surgeon replaced at all? Since the man who was operated on is an important public figure, this delicate case is referred to the Department.The surgeon at the hospital says that the style in which the unknown intruder finished the operation reminds him of the technique of a famous Russian surgeon - yet the man in question would be far too old by now... Nonetheless, Stewart goes behind the Iron Curtain, flying to Moscow to talk to that surgeon, where, after dodging a few KGB agents, he makes an interesting discovery... Meanwhile, Jason follows up another lead that takes him to Istanbul, where his inquiries attract some unwanted attention, so when he is knocked out, he lands in a local hospital, where he too discovers an interesting piece of the puzzle...