Meeting Wes Anderson is like being in a Wes Anderson film. Between the man and his work, there is barely enough space to insert a credit card. It would have to be a very ornate credit card, too, printed in the right kind of font and probably withdrawn from a battered yet expensive-looking tan leather wallet. “Nice credit card,” Anderson would say. “Thanks,” you’d say.

We are talking, suitably, in the well-scrubbed clutter of Claridges. Overblown caricatures of wealth are clipping around on the polished black and white tile floor of the lobby, and Anderson himself is leaning back on a plush sofa which clashes, very slightly, with his neat corduroy suit. His brown hair is swept back over his head, his lips are almost the same colour as his skin, and when he laughs, it sounds like a very neat wheeze. “I do remember,” he is saying, “finding a document on the refrigerator. It was labelled ‘How To Deal With a Troubled Angry Child’. And I saw it, and I said, ‘Well, I guess that’s got to be me’.”

What he is describing, pretty much, is a scene from his new film, Fantastic Mr. Fox, in which Ash, the little oddball fox, comes across a note from his school. Just as easily, though, it could be a scene from Bottle Rocket (1996), Rushmore (1998), The Royal Tenenbaums (2001), The Life Aquatic with Steve Zissou (2004) or The Darjeeling Limited (2007). In conversation, life and film-making seem to blend. An anecdote turns into a scene. A friendship turns into a character.

So it was the father of his old friend and collaborator Owen Wilson who originally gave the speech about privilege that Bill Murray gives at the beginning of Rushmore, and it was Wilson’s older brother Andrew who was shot in the hand with a BB gun in the manner depicted, more or less, in The Royal Tenenbaums. When Anjelica Huston complained about her character in The Life Aquatic with Steve Zissou, it was her exact words of complaint that ended up in the script. And, while it was the director himself who found that note stuck to the fridge, it was his brother Eric who, again like Ash, spent much of his youth wearing a cape.

Fantastic Mr. Fox is, of course, based upon the novel by Roald Dahl. The dialogue is all sardonic and quickfire, and with George Clooney bouncing off Meryl Streep bouncing off Bill Murray, all through the medium of flawlessly animated woodland creatures, the film has one of the finest casts you’ve never seen. Anderson’s films all have moments of haunting and whimsical wonder, but they can seem a bit unbalanced by them. Fantastic Mr. Fox, though, is brilliant. I wonder if that’s because it was made for kids. His intrinsic Wes Anderson-ness is held down, most of the time, like a football in a swimming pool. And then, just occasionally, when there is space, up it will burst.

“You’re talking about the wolf scene,” he says, and he does his neat, wheezing laugh.

I am, indeed, talking about the wolf scene. Spoiler alert: if you’re bothered, skip the rest of this paragraph. Fantastic Mr. Fox has a phobia of wolves. Towards the end of the film, almost at its dramatic peak, one appears on a nearby hillside. Fox panics, shouts, and then suddenly gives it a Black Power salute. It makes no sense at all, and it also makes you want to cry. It’s Wes Anderson all over.

“There were some people who didn’t like the wolf scene,” says Anderson. “In particular one very important person. And he said, I don’t understand what this scene is doing in the movie. And I would always say to him, I’m not cutting it. That scene is why I’m making the movie.”

A greater conscious constraint for Anderson was actually having a plot. “We had a book,” he points out. “Usually in my films... I don’t know, I want to have a plot. But I get to the end, and I look back at them, and I think, no, I’m not sure we did have a plot.” Roald Dahl’s plot required some expanding and Anderson and his co-writer Noah Baumbach thought extensively about how to do this. “I’ve never had a movie before where it felt appropriate to have a kidnapping,” he says, slowly. “But if you look at the Coen brothers’ films, they always have kidnappings. And I think the reason why they do this is because they understand something about movies. The nuts and bolts are helpful. It’s a way to keep the audience from thinking you are getting too far out there.”

Anderson speaks about such things with a sort of overawed naivety. This, along with how young he was when he started out (he made Bottle Rocket when he was 26), is probably why critics invariably describe him as “childlike”. Me, I’m not so sure. Maybe it’s just because he’s older than me, but the style and the well-cut suits are starting to look less like an affectation, and altogether more comfortable. For a long time he wore specially tailored suits, made a few sizes too small but adapted to fit. These days, they’re pretty normal. He still does look young, but there’s an air of the dignified old southern gent about him, too. I wonder if he might be on the verge of going from youth to age, without pausing in the middle.

At 40, Anderson is thinking about fatherhood quite a lot. “It’s got to happen soon,” he says. “My girlfriend and I are thinking that now is the time. Or soon is the time, anyway.” In the past, his girlfriends included Jennifer Wachtell, a Miramax executive whom he cast in The Royal Tenenbaums, and the actress Tara Subkoff. And who is your girlfriend at the moment, I ask.

“Her name is Jumaan,” he says, and he’s tickled by the “at the moment” bit. “At the moment, and I believe permanently. By all indications, it would appear to be an ongoing status. Yes.” They met in New York. Jumaan is from Lebanon and grew up in London, but went to an American school. “Her accent is like she’s from Orange County,” he says. “Hehehe.” Anderson divides his time between New York and Paris, where you can see him fitting in, but these days he’s spending more and more time over here. “I like being overseas,” he says, “but I also like being able to speak the language. And see movies, and understand them.” In Paris, the other week, he saw Quentin Tarantino’s Inglourious Basterds. The German was subtitled in French, and the French wasn’t subtitled at all. It wasn’t easy.

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