A for actor behaving very well indeed

A IS also for Actor, which is what Martin Clunes is - although we tend to forget that readily as his looks and ability to play one of the Men Behaving Badly to perfection have led to him pigeonholed in comedy roles. So casting him as one of this country's most famous serial killers might seem foolhardy, to say the least. It emerges as a stroke of genius, not least because Clunes is a very good straight actor given the chance.

As the writer of A Is For Acid is Taggart creator Glenn Chandler, you could have anticipated that the murders would be pretty grisly. And they are, as John Haigh kills, then bundles the lifeless corpse into a vast drum which he fills with acid to dissolve the body. Well, most of it. The buckets of goo that he's seen swilling down the drain contain lumps of something about which I feel it would be best not to inquire.

The point was, he didn't think anyone could be prosecuted for murder if the police couldn't find a body. He picked up this information during an early spell in jail where he also discovered that a dead rat plonked in jar of acid would disappear like magic.

Chandler's script is an unsensational, matter-of-fact affair that tells a fascinating story clearly and coolly. The reasons for Haigh's unlawful activities remain sketchy. Perhaps it stemmed from his childhood, as the son of Plymouth Brethren who believed they were "God's elect".

Then again, he was a gambler who preyed on rich women (including Celia Imrie at her snootiest) in order to finance his betting. He was a man of contradictions, who coldly murdered again and again - finally owning up to nine victims, several of whose names he didn't even know - but who cried when a dog died.

There was an attempt to tell of his love for a young woman, other than his wife. This was only sketchily drawn in, not so much out of a sense of decency but because this woman never spoke publicly of their relationship.

Even when arrested, Haigh proved his cunning by trying to make out he was insane. He told police he hadn't killed for money or property but because he had to. As a child, he had a dream and knew he had to become a vampire and drink his victims' blood. Given Clunes' persuasive performance as the smooth-tongued killer, you almost believed him.