Thank God for limpets. Without them and their narrative contrivance-pathogens, justice wouldn’t have been served. We’re not talking legal justice of course, the courts of law – pockmarked as they are by fallibility – were proved roughly as useful as a teapot by Cadbury’s in this gripping final instalment to The Escape Artist. Will was no fool, having masterminded a fiendish plan the exposition of which unwound like a particularly memorable Columbo. First, he had to wait for his quarry to go to Scotland (the hoped-for-and-gained ‘not proven’ verdict only being available across the border), then commit the perfect murder, and then use his enormous legal mind to fox judge and jury into letting him go. It all came off without a hiccup too, which was just as well, because the risk the character ran was that of leaving his son without a father as well as without a mother. Will’s profession didn’t escape from David Wolstoncroft’s script quite as cleanly as he did. Just before Foyle’s leg was filled with enough limpet juice to make a signature Rick Stein broth, he responded to Will’s “How do you live with yourself?” by shooting the question straight back at him. Who is more at fault, the unhinged killer or the man who, despite intuiting his client’s guilt, lets him go for the sake of a career win and a champagne toast? After the dreadful inevitability of Foyle’s second dismissal from court, the Scandi-noir-style confrontation at the cabin (smartly directed by Brian Welsh, like the rest of the series) was tense, and, happening as it did about half an hour earlier than expected, surprising too. Why did Will keep appearing to save Foyle’s life, we asked ourselves? Had he experienced a change of heart? Nothing of the sort. It was all part of the plan to inject enough doubt into the jury’s minds so that a guilty verdict would be impossible to return. Will used every trick in the book, from a nationalist appeal to his fellow Scotspeople, to affecting an air of unprepared clumsiness, to those carefully chosen words in his closing speech concluding “you should not convict me of his murder”, instead of “I did not murder him.” The straightforward triumph of the ending was problematic for a character who, in his own words, had lost his heart, his compass, and his anchor not months before. Maggie and Will’s smug-but-captivating dissection of the crime he’d committed was enjoyable, yes, but also a cheap way to treat Kate’s memory. Presenting Will as an out-and-out victor felt insensitive. When you’ve lost what he and his son have lost, can you really ever win again? If there’d been a route to that clever ending which avoided chopping Will’s wife up in the process, the air-punch moment of his having got the baddie and gotten away with it would have been easier to swallow. Overall then, thanks to an engaging story and David Tennant and co. selling every moment like the pros they are, The Escape Artist was tense, engrossing stuff, even if the script did turn out to have a brain where its heart should have been.  Read Louisa’s review of the previous episode, here. Follow our Twitter feed for faster news and bad jokes right here. And be our Facebook chum here.