Camille O'Sullivan & the RSC: The Cat Looks at the Bard

Although Camille has dominated the Fringe's cabaret programme over the last decade – once the star turn of the Spiegeltent, every year has seen her move into and conquer larger venues – 2012 sees her first entry into the International Festival. And while she retains elements of her performance persona offstage – she is charming, witty and passionate about her songs – she is surprisingly modest. She even admits to a little stage-fright at the prospect of her International Festival debut.

"It is really exciting," she says. "And a very different experience. I am returning to Edinburgh in a different guise: as an actress and a co-composer with Fergus Murray." Supported by the Royal Shakespeare Company, Camille and Murray have taken Shakespeare's The Rape of Lucrece and re-imagined it through song and storytelling. 

Best known for her vibrant re-interpretations of songs by Nick Cave, Jacques Brel and other, sometimes unexpected, writers, Camille's powerful voice has the smooth grace of the chanteuse and the raucous energy of rock'n'roll: as the cabaret revival gathered pace across the world, her musical choices went far beyond the predictable cabaret standards and encouraged other artists to imitate her style and ambition.

Director Elizabeth Freestone noticed Camille's ability to evoke the darker, less travelled roads of desire and realised that she could bring her talents to bear on one of Shakespeare's non-theatrical poems. Her last Fringe piece – Feel – proved that Camille could switch between characters and moods fluidly: her unaccompanied version of Brel's Amsterdam is chilling and despairing, while the encore, Cave's Ship Song, becomes an unabashed celebration of passion. The first challenge was to convert Lucrece into a performance.

Reworking Lucrece with Freestone, Camille laughs that she has "taken an epic poem of about one hundred and thirty pages and reduced it to eighty-five minutes and about twelve songs. I play three different people, and I am alone on stage." Shakespeare's poem is intensely serious – it focusses on a violent episode from Roman history, as King Tarquin assaults the virtuous Lucrece, which would lead to the collapse of the Roman monarchy. "I am explaining the story as the narrator," Camille notes. "Then morphing into him and then into her."

Camille's audience in Edinburgh is loyal and even fanatical: they are known for cheering her with some unique noises. "As long as no-one miaows, we ought to be okay," she jokes, referring to their habit of making cat noises in approval. As the previews in Stratford revealed, alongside her work as an actress – she  appeared in the film Mrs Henderson Presents and stage productions of Sweeney Todd –  Camille is more than capable of making the transition from cabaret. Her biggest worry was not practical – "remembering the stuff is not the problem," she confides. "But at least in your own show you can step in and out of character!"

While her run this year in Edinburgh will be shorter than usual – only four nights against her usual month-long marathon – Camille is clearly excited by the challenge. She enthuses about the time working on the production in Stratford. "We were there at the same time they were doing King Lear, and it was wonderful to hear the actor's own natural way of saying Shakespeare's words." The restlessness of her touring schedule and expanding repetoire makes this meeting with Shakespeare a logical evolution: she has frequently identified her enthusiasm for Brel, Tom Waits, Thom Yorke and Dylan as an admiration for their elegant, precise language. On her past record, the Bard may be about to receive a unique interpreter.