A soprano of international renown, co-director Deborah Roberts has herself sung most of the choral works performed under the banner of the Brighton Early Music Festival.

She knows, as a result, that they are urgent, charged works, packed with passionate emotions. But how do you ensure this impact transfers from the 16th and 17th Centuries through to the modern day?

Watching last year's performance of The Full Monteverdi at St George's Church, Roberts found the answer.

Renaissance vocal ensemble I Fagiolini had put Monteverdi's exquisite madrigals into the mouths of six modernday couples, quarrelling at tables in an imaginary restaurant.

The audience, seated among them, became eavesdroppers on shockingly intimate conversations.

"I stood there, transfixed to a pillar, with tears rolling down my face,"

recalls Roberts. "I thought - this is what we have to do now, find dramatic new settings which will bring these emotions to life."

This year's programme, then, includes another multi-media event, once again taking place in Kemp Town's "wonderfully versatile" St George's.

It's called Fallen, receives its world premiere on Saturday and promises to be a thrilling fusion of live music, live theatre and film.

At its heart are the true stories of Camilla Faa Gonzaga, first wife of Duke Ferdinando Gonzaga, and Lucrezia Borgia, the powerful Renaissance noblewoman presented by history as the ultimate femme fatale.

A beauty of the Italian court, Camilla was only 18 when she was tricked into a fake marriage by the lustful Duke Ferdinando and bore him a child. When he got bored, her only option was to abandon marriage and motherhood for life as an enclosed nun.

Lucrezia, meanwhile, living 100 years before Camilla's time, was the daughter of the corrupt Pope Alexander V1 and sister to the notorious despot Cesare Borgia.

Although traditionally held responsible for her numerous husbands' grisly ends, Lucrezia is now more commonly viewed as her family's political pawn.

And she would often seek respite from her situation in the Convent of Corpus Domini in Ferrara.

It is here, the night before taking her vows, that Camilla's troubled dreams stir up Lucrezia's wise but acerbic ghost.

"Camilla is desperate to feel only her calling," explains Roberts. "But she keeps being reminded that she is also a 22-year-old girl who has had a child, who has known what it is to make love to a man, who is oozing with an appetite for life. She keeps praying for deliverance from this boiling' dream."

The "dream", scripted by Fiona Mackie and filmed in advance by the actors Eugenia Caruso, Sue Maund and Jamie McDonald, will be projected on a giant gauze screen.

Meanwhile, works by Josquin des Prez, Claudio Monteverdi, Alessandro Grandi and others will be performed live by the singers and musicians of Musica Secreta and Celestial Sirens.

Cast as the convent sisters and occasionally visible by candelight through the screen, the singers' ethereal female voices will underscore the emotion of the unfolding drama.

"It's very heart-on-sleeve music,"

says Roberts, who as director of Musica Secreta will herself perform.

"The nuns are singing love songs to Christ and they are very literal and in your face about it.

"You can understand why Camilla might be confused by the emotional temperature which this religious music stirs up."

As St George's Father Andrew put it when Roberts asked if he would have a problem with Fallen's more steamy content, "Well, think of the Song Of Songs."