Out in the concrete yard of an East End boozer, the waifish 5ft 9in Ben Whishaw is having a solitary cigarette. Solitary, that is, save for the company of a timid black kitten, which is entwining itself round Whishaw’s ankles, milking his affection. Each seems as delicate as the other. Shortly afterwards, the dashing 6ft 2in Matthew Goode arrives. “Hi Benji,” he shouts across the pub. He then yawns and stretches to reveal a gaze-fixingly taut torso beneath his jeans and T-shirt.

Allow us to present Britain’s It actors of the moment, here playing themselves, then, from Friday, starring alongside Emma Thompson and Michael Gambon in the much-anticipated film adaptation of Evelyn Waugh’s classic novel Brideshead Revisited.

Whishaw — whose 2004 Hamlet was rated up there with Gielgud’s and O’Toole’s — plays the beautiful, charming, but self-destructive Lord Sebastian Flyte, while Goode — variously billed as the next Brad Pitt/Hugh Grant/Rupert Everett — plays his close friend, Charles Ryder, who is torn between his affections for Flyte and Flyte’s sister, Julia. “It’s not really a love triangle,” says Whishaw. “It’s more of a love sea.” And so, with Flyte controversially outed by director Julian Jarrold, there is a stolen sunset snog between Flyte and Ryder, as well as a most gentlemanly sex scene with Ryder and Julia.

It is a measure of how ingrained the story is in our psyches — the 1980s TV adaptation was named one of the greatest British television programmes of all time — that the film has inspired much of the men’s fashion for autumn. The shops are full of 1920s chunky-knit cardies, woollen tank tops and three-piece linen suits. The key affectation, advises Goode, is not a love-worn teddy bear named Aloysius, but a lot of languidness. “With a flower — a peony, maybe — peeping out from somewhere,” adds Whishaw helpfully.

Brideshead aside, Whishaw and Goode are the two extremes of British boyhood. “We are very different people, Matt and I,” declares Whishaw. Easily the posher of the two, Goode, 30, grew up in Devon as the youngest of five; his late father was a geologist, his mother is a retired nurse. He played Scarlett Johansson’s posh English boyfriend in Woody Allen’s Match Point (2005) and can next be seen in the sci-fi thriller Watchmen. While it is Whishaw who is, on screen, always so elegantly wasted, it is Goode who professes an appetite for “getting shitted”, as he puts it. “It’s one of my favourite pastimes. There’s nothing better than hanging out with friends, knowing you’re going to spend the whole night having a drink.” And where can we find him? In tiny, little pubs that nobody else drinks in around Hyde Park, near his home.

Meanwhile, Whishaw, 27, hails from a village in Bedfordshire; his father is a footballer-turned-IT manager and his mother sells cosmetics at John Lewis. He once put cat-breeding on his CV on account of taking in two cats who just kept on having kittens; he still has the original two and, evidently, a soft spot. Trained at Rada, Whishaw has carved a reputation for playing troubled, complicated characters (most recently, an inmate in BBC1’s Criminal Justice). Delicately thin and quietly intense, he can be found in the theatre (both performing and spectating; he is currently on at the National in . . . Some Trace of Her, an adaptation of Dostoevsky’s The Idiot), or with his nose in a book (“I love that bookstall under Waterloo Bridge by the National. I’ll just pick up a book randomly and buy it. Invariably, it’s interesting”), or pursuing his quest for “space and calm” (he is off to Australia in October to do exactly that: “Australia has such a deep impact on me”). Next, he will be starring as the poet John Keats in Jane Campion’s biopic Bright Star.

To Whishaw, acting is not the “cowboys and Indians” that it is to Goode. “I mean, it’s hardly rocket science,” confides Goode. “I love the job, but it’s not going to make me happy, ultimately.” Pause. “Having a family is going to make me happy.” Sorry, ladies, he is spoken for right now, by Sophie Dymoke, who works in fashion. They met on his doorstep — she was laden with luggage, he scooped up her baggage and they were off.

Whishaw won’t be pressed on his love life. Is he single? Is he straight? “I don’t really understand why it’s interesting for people,” he says, politely grinning and bearing the question. But who is he going to take to the UK premiere? “My mum wants to come with me,” he says, “but I probably won’t take anyone. I’d rather be alone and just do my job.”

Bad luck, girls and boys.

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