The Menier has a habit of reinventing its auditorium to suit each new production, but its latest rejig, courtesy of Paul Farnsworth, is arguably its most impressive. Led by an usher, you are shown into a warmly lit, genteel space, a vast apartment full of soft furnishings, Tiffany lamps, stuffed book shelves and Staffordshire pottery, plus a tall Christmas tree.

We are part of the set, sitting around three sides of the room, on sofas and chairs or at tables, like guests at a seance. And the spirit being summoned from the dead is “Tru”, Truman Capote, played by the Modern Family star Jesse Tyler Ferguson (pictured below). He swaggers in, kitted out in a long fur coat and Panama hat, starts talking and hardly stops for the next 90 minutes.

It is Christmas 1975, and Capote’s stellar career has just been partially eclipsed by a scandal of his own making, when he allowed Esquire magazine to publish an extract from his unfinished new novel, Answered Prayers. The chapter that has appeared in print is full of scandalous stories about identifiable members of his circle, some of them his closest friends, notably the women he dubbed “the Swans”: mega-rich socialites who had taken him up as a reliable source of gossip and adoration. Now, stung and outraged, many of them have dropped him.

He still needs his “dirt fix”, though, and is proud to announce he’s been to seven parties in two days, despite having become a pariah. He continues to get phonecalls from Ava Gardner, a fellow Southerner who likes him to go along to Studio 54 as part of her entourage. But he’s off Swifty Lazar’s party list, and his beloved Babe, aka Mrs William Paley, has distanced herself from him for the time being, though she is present in his vivid imagination as a masked figure in a long white tulle skirt and black bustier, with a beaded black jacket over the top. As Babe and other incarnations of ideal femininity that suggest themselves to Tru, Charlotte D’Amboise (pictured below, right) wafts around the set like a ghost, earnest and sad. He puts on “Santa Claus Is Coming to Town”, but she changes the record after he’s gone to Saint Saens’ The Dying Swan.

Ferguson is perfect casting, his accent unforced but adorned with all the odd ornamentation that made Capote’s voice so distinctive, such as his slurred S-sounds and singsong Louisiana cadences. Capote was an acrid wit, captured well here in the zingers recycled in Jay Presson Allen’s script, which also has to deliver a goodly amount of exposition without boring the author’s fans. Mostly it succeeds at this: this version of Tru is never tedious. We find him a defiant pariah, proud of his colourful CV, which ranged from tap-dancing at the age of four in the presence of Louis Armstrong to meeting everybody, from Princess Margaret to Warhol.

Director Rob Ashford exploits the intimate setting by having Ferguson interact with the frow audience, much as Tru might have at a party. It’s the USP of the show that this live interaction is possible, but in other respects, the script (first performed in 1990) doesn’t offer any startling new analysis of its subject and sticks to territory that has now been trawled by a dozen or so Capote films and biographies, not least the recent TV series, Capote vs The Swans. Being in the room where Tru is happening is apparently enough.

So while Ferguson may be an immaculate Capote, the vehicle he is in relies a lot on the audience being devotees who can fill in its blanks for themselves. Those familiar with the bigger picture know Tru is deludedly complacent about his reduced social standing. It will never again reach the heights of his legendary Black and White Ball at the Plaza Hotel’s ballroom in 1966, which he evokes as a warm fuzzy memory of Betty Bacall and Jerome Robbins taking to the dance floor, while Frank and Mia et al mingled with the Swans. “I was at the top, the very top, of my game,” he acknowledges. But the audience has to add much of the remark's poignancy, knowing what Tru doesn't..

Ferguson is good at capturing the small signs of Capote’s decline: the confused muttering to himself, the sad avidness with which he ends up talking on the phone to the young woman at Western Union handling his telegram, who tells him she believes he has been badly treated by his former friends. Capote still has nine years left to live, but his life is never again going to be the storied success of his pre-scandal days. Illness caused by alcohol and drug dependency, alternating with many stabs at rehab, will increasingly be his stock in trade.

But the play doesn’t venture there. So although it ends with a flourish, as Tru and the Swan tango dramatically out of the door, it feels as if the final reel has gone missing.