Whether it’s Hollywood, Pinewood or even Cricklewood, it always baffles me as to why the two leading characters on the silver or small screen* are so unconvincing when they end up horizontal ski-ing.

The thing they are doing together is not the ‘bonkery’ of regular human beings, such as you or I (or maybe I am living in a parallel universe where no one else stumbles, gets cramp or passes gas).

Setting the scene: Benedict and Rosetta have just enjoyed a flirtatious romantic evening at a restaurant or one of their homes. The wine has gone to their heads and now they are kissing frantically. Music plays over the scene – strings, a sixties soul classic or electronic keyboard. Benedict starts to kiss Rosetta on the neck, slowly running his hands down her back towards her perfectly toned derriere.

Meanwhile: Barry and Sandra have enjoyed a few drinks down the Queen’s Head and a bag of chips on the way home. They really fancy each other and have already snogged down an alleyway on the way back to Sandra’s flat. They sit on the sofa (after throwing off the pile of ironing and old tissues) and devour each other’s faces, tongues and all. Barry shoves his hand down Sandra’s top to grab her right boob.

Benedict and Rosetta seem to stand up in unison before Benedict takes Rosetta’s perfectly manicured hand and leads her to the bedroom. The bed is perfectly neat, covered in fluffy cushions; there are big bedside lights, co-ordinated rugs and no clutter whatsoever. In the next shot they are kissing at the same time as lowering themselves on to the bed in slow motion. The same song from earlier still playing and no audible slurping or sighing.

‘Shall we go upstairs?’ Slurs Barry. So the pair stagger up to Sandra’s bedroom. Her bed is strewn with all the clothes she tried on when she was getting ready. There are tissues, magazines, books and a Lego train on the floor. Sandra has to throw the clothes off the bed and kick aside a few teddies to make a safe passage to the bed. As they embrace on the bed, Barry fumbles to undo Sandra’s bra, so she puts one arm behind her back and flicks it open.

Benedict and Rosetta are now both naked, although you cannot see their genitals, just their perfect, smooth, toned bodies – Benedict has a six pack stomach and bulky biceps while Rosetta hasn’t a scrap of cellulite and perfect breasts and a flat tummy. Benedict writhes on top of her and she throws her head back sighing ‘oh, Benny, oh Benny’.

Barry and Sandra are still struggling to disrobe. Barry trips over trying to remove his trousers and smashes something on Sandra’s dressing table. Sandra lies on the bed and manages to kick her knickers off so that they fly across the room, meaning she probably won’t find them in the mess for another two weeks. Barry dives on to the bed and directs her to his member so that she can give him a blow job and stop the beer-induced floppy.

Benedict and Rosetta are still ‘making love’ perfectly framed by silk sheets. Now the beautiful Rosetta is astride Benedict, but the sheets somehow cover her pubic mound. Her long glossy blonde hair is still perfectly styled as she throws her head back in ecstasy, exclaiming ‘Oh God!’

Sandra has rescued Barry’s hard-on and they launch into penetration, but five minutes later Sandra shouts: “Stop! I really need the loo.” So she has to run out of the room, quickly pees and takes this opportunity to remove her contact lenses, before dashing in and trying to resume what they started. Barry needs a quick ‘blowie’ to rouse him again and off they go. Their rounded bellies slap against each other and everything wobbles and jiggles, particularly Sandra’s boobs and she jokingly rubs them against Barry’s face.

Benedict and Rosetta are way ahead now – lying in each other’s arms, blissfully, occasionally taking sips of the champagne which has somehow found its way into the bedroom (I don’t remember seeing them bring it in earlier). They talk about how their eyes met across the park and taking a trip away somewhere together.

Barry and Sandra are still going strong, testing a few positions before Barry comes while taking Sandra from behind and collapses on to the bed. He then lets out a fart so loud that it vibrates through the bed and almost makes the walls shake. ‘Oops, sorry,’ he says, ‘must have been that jumbo sausage I had earlier.’ Sandra can’t hide her little giggle which quickly vanishes when the smell reaches her nostrils.

Benedict and Rosetta have fallen asleep in one another’s arms, romantic music framing the scene. The silk sheets seem to have magically stuck to Rosetta’s breasts (or her breasts have Velcro nipples). No snoring can be heard and they still look as perfect as they did at the beginning – hair neatly styled, Rosetta’s lipstick and mascara are still both intact.

Barry and Sandra had a sweaty cuddle, but are now sleeping at opposite sides of the bed facing away from one another. They tried to lie in each other’s arms, but after five minutes Sandra’s stiff neck flared up so she had to move. She also sneaks another trip to the bathroom and gasps at her reflection – her hair is bedraggled and her eye makeup is smeared all over her face so she looks like she has been in a fight with a pen. She tries to clean the worst off with a flannel and sneaks back into bed with a now snoring Barry.

Benedict and Rosetta can no longer be seen – an upbeat 80s hit is now playing and the screen is covered with film credits. They got their rose-tinted, sugar-coated happy ending, so no one needs to know what happened next. Unless they decide to make a sequel.

*I’m talking mainstream movies, not porn here – I’ll save that for another time.