If you have a guilty secret, don’t risk driving on a dual carriageway. In fact I would stay off the road altogether, if I were you. Part way through Collision (ITV1), a gripping five-night drama based on a multiple pile-up on the A12, I was ready to flog my car on eBay and shred my driving licence.

For this was some accident: tyres and metal spun at high velocity and with sickening impact. I watched it twice. Perhaps I am a sad rubberneck, but I wanted to check out the cause and chain reaction.

And that’s just what Detective Inspector Tolin (Douglas Henshall) did, using photographs to reconstruct the accident. He even paced the road itself. By now I was certain: I would never drive again.

But this was more than a multiple motorway pile-up. There were colliding worlds as paths criss-crashed, with the fall-out that followed from secret lives exposed like physical wounds. Strip tease-like, each episode tantalised by revealing more of the moments that led to the big bang. One couple were smoking hash. High on weed and speed, they accelerated towards death.

White-van man Danny’s Amsterdam trip wasn’t a tulip tour either. Human cargo was his import. While Danny fled, an illegal East African immigrant was left trapped in the bottom of the transporter. As his wife worried, he lay dying, entombed in a white black hole.

Karen had copied her bosses’ files about secret chemical weapons for an on-the-make, fake journalist before the fateful trip. She survived, only to be murdered, not bathing but drowning in a bubble bath of blood.

Tolin had that police officer intuition that screamed everything was wrong when all around were deaf to the problem. But he was hard of hearing when it came to personal relationships with his female colleague. All TV detectives seem to need personal counselling these days. No wonder police costs are rising.

But Tolin’s wife had been killed by a drunk driver, leaving his daughter disabled too, on the very night he had been cheating on his wife. The driver’s attempt at forgiveness almost led to Tolin throttling him to death. Restorative justice isn’t meant to work like this.

The only apparent false note - the unlikely relationship between a wealthy property dealer and the service station waitress - was another deliberate twist, for we discovered he was really just a fantasist. She wanted to escape a dreary, dull future and dreamed of sitting above a foreign city listening to its beat. The Eurostar tickets he bought weren’t wasted when, jilted, she decided to break free and flee.

There were more characters than in a Dickens novel and more plots than a Cabinet coup, all inter-connected. And the collision was caused by the swatting of a wasp. Roll on my free bus pass. Anyone want to buy a Mazda?

Ray Tarleton is principal of South Dartmoor Community College in Ashburton, Devon.