Grace review – a twisty race against time for John Simm's fading detective

John Simm is one of those actors who makes you think: what must that be like? What must it be like to be so good at the thing you do that, when you come along, everyone just relaxes? To be so good that everyone knows they are in safe hands, knows they are going to be shown something great, knows they won’t have to mess about trying to make a little look like a lot.

For viewers, he turns up and you just … believe him. You know he is an actor – you have seen him play loads of different parts, with the same face and everything – yet you accept him in the new without a moment’s hesitation. It is sorcery, really.

And here he is again, doing his quiet, unfunky, wholly credible thing, in Grace (ITV). It is a two-hour adaptation of the first book in the Peter James series about a detective superintendent whose star is on the wane, by the creator of Endeavour, Russell Lewis (also known for his work on Morse and most of the other good TV things you remember John Thaw starring in).

When we first meet Roy Grace (Simm), he is working on cold cases in a back office, his reputation having taken a battering after his last case, which garnered unwanted headlines when the press discovered he had asked for help during the investigation from a medium. Again, it is a measure of Simm’s credibility and enduringly connective everyman quality that this revelation doesn’t immediately make you roll your eyes and lose all sympathy.

Grace’s friend and colleague DS Glenn Branson (Richie Campbell) brings him out of his cold case cupboard to help with a missing person investigation. A stag party was killed in a big road traffic accident – the groom, Michael (Tom Weston-Jones), was not among them and hasn’t turned up since. This, we learn more swiftly than the police, is because the partygoers had thought it hilarious to prank the stag by burying him and a walkie-talkie in a coffin nicked by one of the bantering fools from his place of work. They stuck a piece of rubber tubing in as an air supply and then hightailed it down the motorway, drunk as skunks. God, I hate people. Even in fiction.

It looks, initially, to be a simple race against time – and against this viewer’s choking fear of asphyxiation – after a mysterious figure withdraws Michael’s tube. Meanwhile, Davey (Cian Binchy), a learning-disabled man who picks up the other walkie-talkie, thrown to the verge by the accident, is murdered before he can tell anyone about the new, distressed friend he has made on the other end of the line.

The plot becomes rapidly and pleasingly complicated without losing any sense of narrative. There is a suspicious best friend and business associate (Matt Stokoe) and a grieving fiancee (a fully realised character, incidentally, even before she moves from the periphery, played by Alisha Bailey). There are millions of pounds in an offshore account, a pivotal bracelet, a pair of secateurs and a bloody threat in a padded envelope. Add in a missing social media presence and a dash more murder and everything clicks into place in an immensely satisfying way.

There is another visit to the medium (Adrian Rawlins), too, but as the resolution of the mystery doesn’t depend on anything supernatural, I am going to let it slide.

Underlying it all and giving some emotional heft to proceedings is the disappearance six years previously of Grace’s beloved wife, Sandy. (If I know my Chekhov’s gun rules, this will probably give rise to a story or two in instalments to come, should the appetite for this opening episode grant us such a boon.) She left for work on his 40th birthday and hasn’t been seen since. There was no note, no suggestion of suicide or foul play – she is just gone. The scenes that concentrate on this – dream sequences, Grace’s attendance at a support group, his communing with missing-person cold cases in his bleak little office – are clunkily scripted weak points. The engine stutters, but it purrs along so smoothly the rest of the time that it hardly matters.

An adaptation of the second book in the series, Looking Good Dead, is due later in the year. I have looked into my crystal ball, consulted with the spirits and say we should all look forward to the day.