The Magician's Key

A passenger plane carrying Chinese illegals docks at Dipton airfield, and within minutes an argument ends with a Triad member beaten to death. The murder ties the operation to the Belgian embassy, which is where the trouble really starts. Commissaire Henri Lannermann is supposed to be helping; instead he is unhelpful in a way that reads as untrustworthy, and Cade has to work around him. For a show that usually stays on home ground, the geography alone is a statement.

Triad gangsters arrive in Eastland to avenge their man, and the threat stops being diplomatic. Meanwhile Davies uncovers a bogus doctor running a private business on NHS equipment, and Cade has to organise a security operation for a royal visitor on top of all of it. The hour stuffs three plots into one and mostly keeps them from tripping over each other. Davies's find is the kind of small, grubby crime the series does well, and it sits oddly next to the international stuff. The plane itself, once the killing happens, becomes the least of anyone's problems.

T.P. McKenna's Colin Fowler, Karen Archer's ACC Anne Stewart and Douglas McFerran's Det. Insp. Underwood work the Eastland side. Tony Xu's Zhao Yuhui, Philippe Smolikowski's Phillipe Loral, David Forman's Cheng Rui, Robert Demeger's Superintendent Wilkins and Simon Slater's David Kendal round out a cast that does a lot of name-dropping in a short time.

Jeffrey Caine and Ray Jenkins wrote it, A.J. Quinn directed.

The title has the right idea. Everyone here is holding a key that opens someone else's door, and nobody trusts anybody with it. The embassy and the Triads are doors; so is the bogus doctor. Cade spends the hour trying keys in the dark. It is not the show's smoothest hour, but it is one of its busiest, and there is a real pleasure in watching him keep his feet. The royal visitor is the one piece of ceremony the episode cannot postpone, and it hangs over everything like a deadline.