Dreaming that you have woken up is more than a bit odd. It’s at least as unsettling as catching sight of the back of your head in a mirror. Perhaps more so.

I imagine that trying to solve a murder mystery is a bit discombobulating too. I’ve been known to wake up in the middle of the night in a blind panic because I wasn’t sure if the new sofa would fit through the front door. Tracking down a killer must be at least as bad as that.

So you have to feel for LA homicide detective Michael Britten. In episode one of Awake he is involved in a terrible car accident and wakes to find that his wife was killed in the crash, leaving him as sole carer for his teenage son.

Then he wakes up again to find that his son was killed in the crash, leaving him alone with his wife. Which reality is the real reality? We aren’t sure, and nor is he.

There are some cues to tell you which world Britten (British actor Jason Isaacs) is in at any given time. Mainly some artistic colour grading. One reality is a little on the blue side and the other slightly more orangey.

Interestingly, the crimes that Britten investigates in one world have resonances in the other. They’re not the same crimes, but there are similarities that fuel extraordinary leaps of deduction.

Every cop show needs a gimmick, and this parallel universes trick is better than most. It has all the intriguing pseudoscience of Life On Mars with none of the ‘Oxford Bags and Tank Tops’ comedy.

You might see Britten’s regular visits to a psychiatrist in both realities as a simple plot mechanic, to let the writers deliver big chunks of exposition. But the differing characterisation of the two analysts (one’s sympathetic, the other is rather hard work) lends an extra dimension to Britten’s plight.

Laura Innes, ER’s Carrie Waver, turns up as Britten’s police captain in the orange-flavoured reality. I still find it a bit jarring that she doesn’t have that limp she executed so convincingly in ER.

As the series progresses there’s the suggestion of an over-arching conspiracy threading the series together. Awake is an interesting idea, done well. But it’s not the kind of thing you’ll be able to join in on later in the series.

Give the first episode a go this evening, if you can. And don’t, whatever you do, nod off half-way through.