In Guy Ritchie’s Mayfair pub, the conversation has turned to coffee. Apparently, at home, Ritchie struggles to get good foam, even though he uses the same type of machine that has just created our pair of frothy drinks. Whether his wife, Madonna, has the same problem, he does not say. He calls over one of his serving staff to ask their advice.

“He’s called Lord Henry,” whispers Ritchie as the waiter approaches. “An interesting nickname,” I suggest. Ritchie shakes his head. “No, he is a lord. The son of someone-or-other. It’s funny, the other chap he works with is called Mr Soho, and he always defers to Henry, calling him ‘Your Lordship’. It’s caught on; now I’m calling him that, too.” With names like Lord Henry and Mr Soho, this pair could have been plucked from one of Ritchie’s crime movies.

“It’s funny you should say that,” continues the 39-year-old director after sending Lord Henry to find the secrets of fine foam, “but the very reason I wanted to make my new film was that I’ve lived in London for almost 40 years now and in that period of time it’s been impossible not to have observed the entire spectrum of the social ladder. Lord Henry and the Soho barman. I like that. I like that about England because it’s complex within its social fabric; I hope the film shows that.”

The film is RocknRolla, which features the likes of Gerard Butler, Thandie Newton, Tom Wilkinson and Jeremy Piven, all of whom prove dubious sorts who manoeuvre their way through the seedy underbelly of the London crime world, a realm populated by billionaire Russian mobsters, old-school London villains, crooked accountants, corrupt councillors and a brace of sadistic East European assassins. It is good fun.

It is also Ritchie’s first feature film for three years. Given the critical mauling suffered by his last two, Swept Away (2002) and Revolver (2005), is he nervous? “Not at all,” he smiles.

“This will be much more popular than Revolver. It’s simpler and it’s fun. After Revolver, I’m not sure that everything needs to be an analysis of the deeper motivation as to why we get up in the morning.

“The majority of times I go to the cinema, I want a bit of everything. I want to be challenged intellectually, and then again I don’t want to be too challenged intellectually.”

Lord Henry has not yet returned to answer the riddle of the frothy coffee. As we sup our drinks, Ritchie talks about his wife, although, not surprisingly, he will not discuss tabloid rumours which suggest that his seven-year marriage is set to implode.

“I believe my wife to be very creative so of course I’m interested in how she thinks,” he says, “and there seems to be no end to the desire to be creative; I find that invigorating and interesting.”

And do they still gel intellectually? “You know, you have conversations, some deep, some shallow,” he smiles. “That’s the same in everybody’s relationship.”

Whether his relationship will last, only time will tell, but rumours suggest that the couple are trying to remain buoyant for the sake of their children — adopted son David (two), Madonna’s daughter Lourdes (11), and their own son Rocco (seven) — and so as not to detract from their forthcoming creative ventures, in Ritchie’s case, RocknRolla, in Madonna’s her world tour.

Whatever the truth, Ritchie needs a box office hit, and the early response among critics suggests that RocknRolla is a return to form.

It is certainly a return to familiar territory. Ritchie’s two early crime romps, Lock, Stock & Two Smoking Barrels (1998) and Snatch (2000), remain his most popular films, so it is no surprise to find him visiting old ground. This time, however, his directing style is simpler — gone are the fancy shots and quick-cut editing. “I feel that sort of film has had its day,” he says. “It felt fresh 10 years ago but I’m not sure how fresh it feels now. I love the crime movie, though, because it’s like the western, in that it’s a genre against which you can tell any kind of story.

“Originally, I was interested in making a commentary on how London has changed in the last 20 years and you just need to pick a genre in order to make that commentary. This could be a modern western.”

As we talk, he defends his two critical failures. Of his seven cinematic offspring, he regards Revolver most fondly, and believes that too many people wanted both that film and Madonna-vehicle Swept Away to fail.

“The week Revolver came out, there were far worse films at the cinema, but all the crap got heaped on to me,” he smiles. “And again Swept Away came out and clearly wasn’t as bad as some of the films that came out that week!

“Some stuff I can tell is vitriol. There’s a hidden agenda. People aren’t being honest with themselves when they launch into some critical vitriol because I fancy I know what I’m doing behind a camera — I’ve been doing it for a long time and I know a lot about it — hence I probably know more than most critics.

“I can see the chin maybe got stuck out a little further than it needed to,” he concedes, “but we made Swept Away as a low-profile movie, for $5 million.” He shrugs. “But, hey, I don’t think there’s anything you can do that’s low profile with my missus.”

Ritchie’s next project will see him direct the mercurial Robert Downey Jr as Sherlock Holmes, in a story drawn from a forthcoming comic written by Lionel Wigram, a former Warner Bros executive who is set to produce the film. Ritchie also harbours hopes of shooting a children’s movie. It’s a dream he has fostered for some time; he and Madonna once wrote one together.

“Honestly, I can’t remember its bloody name,” he laughs, “it keeps changing. But I will certainly end up making a kids’ movie at some point. If you have kids, you end up watching a lot of kids’ movies and often you find some of their movies are infinitely more sophisticated than adult ones. What springs to mind? The Incredibles. I thought it was smart filmmaking, and Ratatouille was bloody good.

“They are films for everybody, and that’s what good films should be. We are all philosophers. It’s impossible to live and not be a philosopher. Life is philosophy.” He smiles. “It’s just that some people have thought about some things more than others.”

Personally, I’m now thinking about Ritchie’s coffee problem. Maybe it’s because Lord Henry is approaching. Does he have the answer to the mystery of the missing lather?

“It’s down to how you grind the coffee; you need good technique to get a finer grind,” Henry says politely. Ritchie is satisfied. He pauses briefly: “Thank you, your Lordship.”