Imagine a voiceover. It's me, only it's not really me, because I have a voice like Bob Hoskins. And I'm saying this: “It's 7.30 on a Sunday morning and I've just been flashed by the Old Bill. This is bad news. There's a bag of guns in the boot, a bag of cash on the back seat, and I'm late for a job.”

Luckily, the police don't make me stop. So, two minutes later, I'm pulling up on a double yellow line in Soho to pick up a man carrying three ominously large black bags.

“Hop in,” I say, exhausted already. “You slaaag.”

Freeze the frame. Write the word “Earlier...” across my forehead. Give me a sting of music, and maybe some sort of crazy screenwipe, and I'll explain.

Guy Ritchie's film RocknRolla hits cinemas on September 5. It may be a return to form. At a press conference, Ritchie was asked whether he had been under studio pressure to recreate his more successful earlier efforts. “Yep,” he said, cheerfully. So expect guns, ethnic minority gangsters and novelty-themed hitmen. There will be a split-screen every time anybody uses a telephone, a voiceover and some kind of convoluted plot that leaves everybody but the hero dead. And, just before they all die, expect a montage, probably set to the theme tune from Zorba the Greek.

God, I hope so. Hardened movie buffs may spit when I say this, but I love Guy Ritchie films. I love the way they daaaahn't mess araaaahnd. I loved the messy simplicity of Lock, Stock... and I loved the style of Snatch. But then it all went wrong. Swept Away was a disaster. It didn't have any guns at all, it went straight to DVD, and you sensed that he only made it because Madonna fancied a beach holiday. When Revolver was about to come out, and the reviews were godawful, I was terrified. The world needed another Guy Ritchie film. It looked as if Ritchie wasn't going to deliver.

So I did it myself. I teamed up with a television journalist called Jon Gilbert and, in a single day, and with a budget of £50, we made a Ritchie spoof called My Daily Monkey. You can still find it on YouTube. Now, three years later, Ritchie is back. I'd like to trust him. But I don't. So I've got to do it again.

Unfreeze. Cut back to that double yellow in Soho. That's us. In the back we absolutely do not have an unconscious traffic warden. Just so you know.

It's not easy to parody a film that you haven't seen. The trailer doesn't even explain why it is called RocknRolla. Speculation is that it is something to do with his two children, Rocco and Lola. I don't have any children. I was stumped already.

Then, two weeks before our filming day, Gilbert and I met for a pizza. I had ham and olive. He had bacon avocado.

“GuacaMola,” I said, suddenly, and we were off. It was to be standard Ritchie fare, but with avocados, instead of drugs. Our ethnic minority gangsters would be from wherever avocados come from. Our novelty-themed hitman would be a gardener. We were very excited.

Two days later I had a script. Basically it was the same script as last time, with slightly different decoration. Plus it would need a bigger cast and a bigger budget, and it all made slightly less sense.

“Oh,” said Gilbert. “It's a sequel.”

Second films are hard. I see that now. The pressure is really on. Our last film was supposed to be a silly little thing. Instead, the project soared. We ended up with a cast of four, one of whom (Dave Legeno) had actually been in a Guy Ritchie film (Snatch). We had filmed in Stringfellows and at a cage-fighting match. It generated record hits for Times Online and we were interviewed on the local news. As a result, the paper is now prepared to entrust us with a bigger budget. A much bigger budget. Maybe as much as £100.

Poor Guy Ritchie. I can see how he must have felt. Success changes you. Since 2005 we have come a long way. You might have seen Gilbert presenting, on the ITV News or London Tonight. Me, I have a full-time job at The Times. There's a lot of expectation. I started to crack. Props, locations, it all became a whirlwind. And I still didn't know where avocados came from.

Suddenly, we needed a cast of seven. Last time, we managed to fit the whole production into my Mini. This time, I realised, we were going to need to criss-cross London in a convoy of three cars. Gilbert kept phoning me up and saying such things as: “Dave Legeno is busy being a werewolf in Harry Potter!” and “Have you called Peter Stringfellow yet?” and “My friend JD is going to lend us his Ferrari!” And we still had to film it in a day. I'll admit it, I was pretty stressed out. I mean, I didn't take up kabbalah or anything, but still. It was bad.

A word here, about our plot. Our hero is Jimmy, a rock star down on his luck. From the trailer for RocknRolla it looked as if we need one. Not sure why. Haven't seen the film.

A Guy Ritchie film traditionally also requires two sets of gangsters, one from London and one from somewhere else. Our latter set were from Avocasia, the minor breakaway region of Russia which, as you will know, is where avocados come from.

So, in GuacaMola, our hero is sent on an errand that goes wrong. He is supposed to take a bag of cash to the Avocasians, and a new hybrid superstrain of avocado (the GuacaMola) to the Cockneys. He gets this the wrong way round. What with the Avocasian avocado crop having failed some years back, forcing them all into a life of crime, this is a gross insult. Thus, gang war ensues. There's also an accountant called Doris. No special reason why.

We filmed it all last Sunday. The first scene took place at The Times. Andrew Watson, a graduate of Bristol Old Vic drama school and star of stage, screen and, at one point, EastEnders, was playing the rock star. He had to stand in a lift, naked except for his underpants and sunglasses, holding an Uzi.

“Why?” he asked.

“Read the script,” I suggested.

Watson didn't feel the script answered his question. But there were other concerns. The lift kept soaring off to the sixth floor, where the paper's executives have their offices. That's what really makes a career, a naked man meeting your boss, while holding an Uzi, saying: “I'm here with Hugo Rifkind”. Outside the lift, there were lights, stands, microphones. Last time around, Gilbert just had a camera. That was my first inkling that we might have got a little carried away.

The next scene was in times2. Elizabeth Conboy (Moving Wallpaper, Holby City, The Bill) played Doris, the accountant. She's the one who sends Jimmy off on his errand, with the GuacaMola. “This is no ordinary avocado,” she purred. Elizabeth also does voiceovers.

Next stop was a grafitti-coated alleyway in Southwark for a few running scenes. By now Watson was in a fur coat, kindly lent to us, like the guns, by Angels Fancy Dress (www.fancydress.com) on Shaftesbury Avenue. Here we were joined by Ian Lilley, who specialises in musical theatre. He was playing Henchmen 1 and 3.

Henchmen 2 and 4, I played myself. No lines. According to pretty much everybody who saw it, the worst thing about My Daily Monkey was me. And to think I once had the temerity to sneer at Ritchie for casting his wife.

Last time around, we did everything in a single shot. I told them that, when I went on the TV news. “How did you make it so quickly, Hugo?” they said. “We didn't do any retakes,” I said. Then I said it again. Maybe 16 times. They kept asking me, from different angles. They didn't get the irony.

This time - and I say this with full respect for the man and his craft - Gilbert seemed to have gone a little nuts. If he didn't get the shot he wanted, he made us do it again. And again. He wanted quality. He wanted art.

“You aren't dating a pop star, are you?”

“Eh?”

Never mind. Anyway, we were on schedule. At midday, we were off to Gleason's Boxing Gym (gleasonsboxinggym.co.uk), by London Bridge. You have to have boxing in a Guy Ritchie film. It's virtually the law. Here, our London avocado kingpin, Green Fingered Gary (alliterative names are very important on Planet Ritchie), played by Daren Holmes (EastEnders, A Touch of Frost, Rome) battered a punchbag and shouted at his henchmen. And then he gorged on an avocado and menacingly held a kitten. Various bits of Gilbert's huge and daunting kit kept breaking down, but all was still going roughly according to plan.

It was afterwards, with a thump, that the wheels started coming off. Cast and crew in convoy, we arrived at a set of arches in Southwark to film the finale. Gilbert's friend John Doherty (a GP from Windsor) had arrived, as promised, with his Ferrari. According to the script, the Gardener (our horticulture-themed hitman) had to club Jimmy unconscious and chuck him in the boot. A Ferrari doesn't have a boot. There's just a wee hole under the bonnet. Schoolboy error.

Worse still, we didn't have a Gardener. Our actor was a no-show. According to his CV he was also fully trained in ninjitsu, so I wasn't going to make a fuss. Still, it was a blow. I thought of all those real gangsters, playing bit parts in all those Guy Ritchie films, and I felt a new respect. Balls of steel, that man.

Thank God, then, for The Times photographer Chris McAndrew, who, by a stroke of wonderful luck, looks a hell of a lot like a gardener.

“Club Andrew with that shovel and chuck him in the bonnet,” I told him, and he did, with vigour.

An hour later, Chris was lying on his back in the dirt with the rest of us, clutching a plastic shotgun and smeared with avocado. That was the second time we saw the police. They cruised by at 5mph, nodded, and they didn't even wind down the window. Southeast London. Jesus. Hard as nails.

By now, we all hated avocados. Loathed the things. We had them in our hair, in our clothes, in our eyes. And we still didn't know where they came from. Somebody thought it might be Mexico.

One more scene, at the lavish Stringfellows Angels club on Wardour Street. This was with Victor Gardener (Emmerdale, Murphy's Law, recently played Macbeth), the scary giant of a man we had cast as Uri, the chief Avocasian. We were really late. It took hours. And I have never seen a man look at a vegetable with so much passion. Watch it. See the fury in those eyes. When that man crushes an avocado, it stays crushed.

Outside, it was Soho's Gay Pride weekend. We'd forgotten about that. If you were there, perhaps being proud, and you wondered who those exhausted, faintly Russian-looking people were, who staggered past with plastic shotguns, a chainsaw and a Fender Stratocaster, well yes, that was us. We went to the pub, and none of us had the faintest urge to start a fight or set each other on fire. We were too tired

I haven't seen the film yet. At the time of writing, Gilbert is still doing the edit. But there and then, I decided it was going to be brilliant. It didn't matter if RocknRolla was wonderful or woeful. The world would have a new Guy Ritchie film.

“And,” yawned Gilbert, “this time it's in HD.”

“Shut it,” I said. “You slaaag.”

Explore Film

• Film Reviews

• DVD

• Oscars

• Bollywood

Editor's choice

• The 50 Biggest Movies of 2009
• The other side of Angelina Jolie
• Quantum of Solace