Your flashback needs a flashback.

A red sports car hurtles along a country lane, the radio playing a Blondie track. But this is not enough to specify the time. The two women in the car are arguing over the blond passenger's apparent inability to read a map. The brunette driver angrily drains a can of beer, hurls it away vehemently. One cut as the empty can flies over a fence. One more cut, and it rolls to a stop in the grass, revealing a sell-by date in May 1988.

There you are. Fifteen seconds into the sequence and we already have a clear sense of the women's dynamic -- it will be crucial -- and we know this happens in the past, so it's undoubtedly backstory, told with startling economy.

The use of the can to establish the date so quickly and unambiguously is brilliant. No, it's contrived and ham-fisted. No, it's written (and produced and in this case directed) by David Renwick, so it's tongue-in-cheek.

It's from the "The Judas Tree, " the April 2010 feature-length episode of the clever and hugely entertaining television series "Jonathan Creek," which since 1997 has featured endearing Alan Davies as the scruffy, beduffled but rarely befuddled expert on stage magic and illusions. And we have to wait until the end of the program to know that Renwick's rich flashback has fooled us. (And in this case, it fools Jonathan.) We're so taken by the economy of the exegesis, by the way the story hits the ground running, by the way he obeys the rule to start as late as possible in any scene, by the uncanny events that then unfold, that we forget to ask an obvious question: what happened even earlier? The swiftness of the story deceives the memory.

Left, Alan Davies. Right, Alan Beechey (in 1975). Scary, huh? And I had a duffle coat.

Yes, the reach of Renwick's writing often exceeds our grasp of the events, but what's a mystery for? The apparent contrivance and coincidences of his baffling set-ups are whittled down so satisfyingly over the course of an hour and a half, that we can easily brush off the traces that remain. These are good mysteries and great visual story-telling. And funny with it. Catch them if you can.