Review: The Reckoning (BBC1) This is Coogan's Hannibal Lecter, what he'll be remembered for most

There must be better ways to spend a Monday morning from 6am than this. Every glint of the bling. Every crackle of the polyester tracksuit. Every dodging of an incriminating enquiry. Nah, you’re wrong, guys and gals, it was all just a bit of fun. Just some messing about. Just Jimmy being Jimmy.

By better I might have meant fun, if Jimmy Savile in the course of this gruelling, gut-churning drama had not contaminated the word. By better I really do mean less horrific than four hours of a sex monster getting away with it.

But if I hadn’t watched The Reckoning I’d have missed Steve Coogan’s astonishing portrayal. Publicity stills hinted at it being a terrifying tour de force. How he held a cigar suggested this, the haughty, head-back way he sat in a chair.

Then there’s the voice. Before the truth about Savile the predator emerged, back when he was never off TV, everyone could have a go at impersonating him and most did. “Guys and gals … as it ’appens … now then, now then.” Saville’s schtick was so familiar, and so easy. A terrific mimic in comedies like The Trip, Coogan mostly avoids the man’s calling-cards because he’s going for the Savile we didn’t know until it was too late.

He perfectly captures his subject’s unashamed, relentless evil. It’s there right at the start when disc jockey Savile at the northern dance hop orders a ticketless lad to be beaten up. And it’s there right at the end when he’s being driven home in his Rolls-Royce to die there and the hospital mortuary attendant berates him for not confessing his sins during last rites. “Thanks, pal,” he sneers, like he’s done all throughout the four hours, “but I’ll take my chances like I always have.”

Earlier, the attendant had raised the alarm about Savile’s necrophilia, one of many shocking scenes which will play out over the coming weeks while another modern horror story - that of the Yorkshire Ripper - continues at the same hour on ITV. Almost as shocking is the senior nurse’s reluctance to order the beast in their midst off the wards. “I cannot say that to Jimmy Savile,” she protests.

No one could, or would say, anything to Jimmy Savile. Sam, one of four victims bravely acting as narrative devices for the Neil McKay’s drama, describes how he surrounded himself with those who “thought he could do no wrong … people who ran institutions, supposedly educated”.

One of these institutions was of course the BBC who’ve been criticised for The Reckoning omitting the scrapping of a Newsnight investigation into Savile and accused by some of letting themselves off lightly. Well, ex-BBC1 Controller Sir Bill Cotton, who died in 2008, three years before Savile, doesn’t get off lightly. A colleague, Anna Instone, is vehemently against his recruitment to new show Top of the Pops - “Vain, overbearing, untrustworthy … an absolute s**t” - but she’s ignored by Cotton. And later, when dark rumours begin to burble, he tells her: “All I know is that Jimmy Savile is a brilliant talent and we must look after the talent.”

He was certainly brilliant at manipulation, achieved through threat and charm. One minute it’s kisses right up the arm and “A princess like you?”. The next “Do you know who I am?” with Savile warning Cotton that he owes his top job to the madcap, peroxide chronicler of the Hit Parade.

Quizzed in a lawyer’s office after the death of a 15-year-old girl whose suicide note alleged sexual assault by a DJ after TOTP, Savile curls that lizard’s lip and informs the brief: “You really need to have a think about who you’re talking to.”

Watching all four hours back to back, The Reckoning can seem like one big, gruesome boast-athon from Savile: “I’ve kept the company of queens, princes, popes and presidents … Darwin, Dickens, Disraeli and the Duke of Wellington all parked their a***s in this chair before me … I’ve just come from eggs and chips with the Kinks.”

But if you momentarily forget some of the atrocious attacks it’s probably because you are attempting, desperately, to wipe them from memory. For Savile’s Travels he meets a girl in a wheelchair who tells him she hardly has any feeling in her legs following a swimming-pool accident. This is his cue to stick his hand up her skirt. She can’t protest because he’s recording, and reckons she’ll be happy enough to have a song request played.

Then there was Jim’ll Fix It. Savile sat back in his throne, “dream-maker to the nation”. Another of the drama’s victims, Kevin, tells how as a Boy Scout he was lured to a dressing-room with the promise of his own special badge. “Jimmy Savile groomed us all,” he says.

He wormed his way into government, too, and there’s a jaw-dropping moment at Chequers, invited for Christmas by Margaret Thatcher, when he butters up the PM as she’s basting the turkey, telling her he approved of the sinking of the Belgrano during the Falkands War - all part of his sustained sweet-talking to secure a knighthood.

There’s flattery, too, for Dan Davies, interviewing Savile for the book In Plain Sight that forms the basis of the drama with its subject addressing him as “Dr Wordsmith”. (In the 1980s Savile called me “Captain Truth”, this was when I was the lowly Evening News Charity Walk correspondent for his annual visit to Edinburgh as the event’s cheerleader).

Davis is played by Mark Stanley and there are fine performances all round, not least Gemma Jones as Savile’s mother, “the Duchess”. Watch, if you can bear, for the victims. And for Coogan who’s probably going to be remembered for this above everything else, just as Anthony Hopkins can never quite shake off Hannibal Lecter.