John Carter battles Martians with a loincloth, a chiselled torso and the ability to jump really high.

The John Carter trailer doesn’t give much away in terms of plot. Instead we have epic landscapes, aliens with extra limbs and production design that all looks worryingly Attack of the Clones. Visually, everything’s awesome but there’s not a whole lot of dramatic meat, perhaps because there isn’t enough of it to spare for a trailer.

Step up The Avengers. Sorry, Avengers Assemble , as it’s now called in the UK. The trailer keeps things simple on the story front here too. Lots of heroes we recognise, a Big War, people running scared and Thor’s brother in a mood. But hey, who are we kidding? The film’s going to be a lot of fun and the cutting-edge Computer Generated Imagery is a major ingredient in both John Carter and Avengers Assemble.

As great as CGI can be, it should be possible to wean filmmakers off the visual effects when it all gets a bit too much and audiences start asking questions about who wrote the script. No doubt Hollywood looks after its own with a CGI help group that keeps the afflicted talent away from the prying eyes of Joe Cinema Goer.

I picture a small, characterless room hidden away on a studio back lot somewhere, with a group of depressed filmmakers sitting in a circle with their heads in their hands. A greying man in a checked shirt and comfy loafers agrees to speak. He sighs and strokes his silver beard: “Hello everyone. My name’s George Lucas and I’m a CGI addict.”

There’s a chorus of “Hello George” from his filmmaking friends.

George pauses to collect his thoughts: “Okay, this is difficult… I first started using in the late 90s. My friend Steven said CGI helped on his dinosaur movies and he said maybe I should try it. He said it would… help me at work. At first I just used it a little bit and that was okay. The Special Edition versions of Star Wars had good stories already and the CGI I used was okay too. Then I started work on The Phantom Menace-”

He stops for a moment as he chokes back tears. James Cameron puts a hand on his shoulder and whispers encouragement.

George continues: “On The Phantom Menace I started losing control. I was using CGI all the time. There was just too much going on and I thought everything needed that extra kick. God, I spent so much money! And I started using it to cover up the god-awful story. The plot dealt with intergalactic taxation, for Christ’s sake! My work was suffering but I didn’t care. It was more, more, more. GIVE ME MORE CGI!

“I realised I was hurting the people who loved me. My fans were really upset. The story was all over the place and my fans said I was really testing their relationship with me. They felt betrayed and angry because I was using so much and they felt like I was plundering their childhoods. There was the Yoda thing. Once a muppet, always a mup-”

George’s voice cracks and he wipes away tears with the back of his hand: “And what did I do? I went and made Attack of the Clones and Revenge of the Sith! I thought the answer to my problems was to use CGI even more; can you believe that?? I couldn’t stop, that was the simple truth. God I’m sorry. I’m so sorry!”

He breaks down. James Cameron embraces him. Robert Zemeckis fetches him some water in a little plastic cup. Pixar boss John Lasseter watches smugly as he silently congratulates himself on nearly 30 years of successfully combining CGI with stunning storytelling.

George gets riled: “We need to focus on the stories! Let’s not patronise our audiences! Let’s-”

James Cameron smacks him round the head with a copy of the Avatar 2 screenplay. Lucas sits. A middle-aged gentleman with a square jaw and blonde hair summons his strength and slowly stands, his head bowed. He looks at his colleagues through red-rimmed eyes and speaks: “My name is Michael Bay and I just agreed to do Transformers 4. I’m using too much CGI and I don’t know how to stop. Please help me!”

He bursts into tears: for him, he knows, it’s already too late.