“You know if you kill your father you have to sleep with your mother?”

Well, we’ve been here before. The mother-loving pretty-boy, keen to murder his own father because of the wrongs he feels his mum has been subject to.

And with a cast that includes a post-Withnail Richard E Grant, a post-Rita Julie Walters, and a post-most-of-his-career Denholm Elliot, how can this film possibly fail?

Well, spectacularly, as it turns out.

There is nothing to recommend Killing Dad. Unless you’re a fan of grim, brown reminders of how depressingly shit the UK was in the late 80s.

Our hero is Alistair Berg (Grant), who starts the film face-down and floating in the sea, addressing the audience in voiceover. How did he get here? Who cares. But since you ask.

Berg is a door-to-door hair tonic salesman (of the type we were simply awash with in 1989… remember how you couldn’t walk down the street without being hassled by blokes carrying briefcases full of crap OH HANG ON THAT WAS THE 1950s). The usually weirdly cool Grant has allowed his hair to be chopped into the worst haircut in history, and his somewhat overripe acting style is in full effect here, and not helped by the ‘do. Berg is a wild-eyed, loose-limbed moron with no redeeming qualities. He’s been brought up by his mum Edith (Anna Massey) after his father Nathy (Elliot) ran out on them when Berg was a baby. And the son has now decided that he must avenge his mother for this slight by tracking dad down and murdering him.

So he sets off for the seaside town where his father was last seen, and much hilarity ensues as I’m sure you can imagine. You can’t? Well try this for size. Berg creates the nom de plume of “Mr Greb” by re-arranging the letters of his name, displayed on his salesman’s suitcase. How’s that for a great joke? Not for this film the opportunity to give him a longer name and thus come up with an anagram that actually makes sense as a surname, oh no. Berg/Greb somehow attracts the attention of every woman he meets, despite having no discernible interest in said females. This includes his errant father’s current squeeze, Judith (Walters) who can’t keep her hands off him, even though he seems continually repulsed by her. His father owns a hideous, human-sized “ventriloquist’s dummy” which becomes a major plot point for exactly the reason you might think a human-sized item would in a “comedy” film about an idiot with murder on his mind. And so on.

As a lot of running about ensues, we are also treated to the continual re-appearance of that 80s comedy staple, the gang of middle-aged “punk rockers”. Including – joy of joys – one who dresses like a 1950s teddy boy. You don’t get funnier or more zeitgeisty than that in 1989.

The entire thing is a genuine embarrassment for all concerned. I’d give some credit to Walters’ drunk acting if I didn’t have the sneaking suspicion she was self-medicating with gin to help get her through what must have been a painful shoot. The film sneaks onto this site due to the darkness of the subject matter and that dummy, which is genuinely unsettling even before someone throws it onto a bonfire.