There have been some really nasty mouths on TV and cinema screens over the years. Hannibal Lecter's springs to mind. Although, to be fair, the gimp mask didn't do him any favours. Batman's bete noire Bane (as played by Tom Hardy) suffered from the same indignity, poor chap. He probably had a lovely smile behind all that leather and metal. That's what his mother said, at least.
Albert Steptoe (remember him?) had a malevolent gurn so loaded it actually made you feel dirty. Not quite as filthy and rotten as Hessian Horseman's ghastly black gnashers in Sleepy Hollow, which made you retch (headlessness improved him no end).
For a more life-like mean mouth, pinched and bloodless and filled with nothing but venom, I always thought you need look no further than Begbie's cruel kisser in Danny Boyle's Trainspotting.
That was before watching Guilt on BBC Two, an Edinburgh-based four-part drama starring Mark Bonnar as Max McCall, a solicitor perpetually on the verge of losing it.
Maybe the perma-snarl is a Scottish actor speciality, like Irn Bru is in the fizzy drink market. They're both livid, anyway.
With good reason in Max's case.
There he was, coming back from a jolly wedding having had a bottle of champagne or two, when his younger brother and designated driver goes and runs over an old man causing Max's top lip to take on the properties of a very thin and angry elastic band.
Jake (Jamie Sives) is all over the place; he's all panicky and muddled, which is hardly surprising given he is sky-high on weed.
Jake wants to do the right thing, Max wants to drive on: these two would disagree about the colour of The Beatles' Yellow Submarine.
"You've got no soul," says Jake.
"You've got too much," Max snaps back.
They duly enter into a spiral of poor decision-making which serves them very badly indeed but works a treat for the plot. OK, it's not the most original set-up of all time: an odd couple crime caper in which the increasingly desperate attempts by the two anti-heroes to cover up their guilt leads them deeper into the mire.
It is often funny, not so much in a Laurel and Hardy "another fine mess" way, more like Noel and Liam Gallagher and their constant sniping and carping.
Max and Jake loathe each other.
They have a long-standing beef, which middle-age has done nothing to quell. In fact, their mutual disregard is just about the only thing they have in common.
Max is the bossy older sibling with all the trappings of success: the flash car, the big house, the expensive clothes, and a wife (Sian Brooke) he considers a trophy but who self-identifies as a sentient human being.
Jake is the "kid" brother who never grew up.
While Max was doing the hard, corporate yards climbing the legal profession's ladder, his younger brother was dreaming of being a pop star. When he woke up a decade later to discover he wasn't duetting with Mick Jagger on a charity single but was actually stony broke with no prospects, he was only too happy to accept Max's offer of setting him up with a specialist record store.
Max is hard, Jake is soft.
Max plays with the big boys, Jake plays records. Max has a lot to lose, Jake couldn't give a damn. Until, that is, he meets the American niece (Ruth Bradley) of the man he ran down.
I will say no more.
Other than, Guilt is very good.
There's a lot of telly about at the moment, but this is a notch or two above most.
Neil Forsyth's scripts are precise and darkly witty, his characters believable and entertaining. Robert McKillop's directing is crisp and evocative.
The cast brings this tale of the Edinburgh underworld vividly to life, playing up to its more surreal elements like Twin Peaks veterans. There's a welcome appearance from an in-form Bill Paterson (Fleabag), while a steely-eyed Ellie Haddington takes on the role of a curtain-twitching, nosy neighbour with whom you would not leave your kids.
Guilt is the polar opposite to the trendy slow-burn box set.
It starts with a bang and builds from there, with a plot that twists and turns like the snakes in Medusa's hair.
My only whinge is four eps aren't enough for a proper binge, bring on season two.
Recent reviews by Will Gompertz