Deadline journalist Andreas Wiseman describes the project as "a feel-good comedy drama described to me as being in the vein of Shakespeare In Love. It tells the story of Handel's canonical piece of music Messiah and its chaotic, spectacular first performance."
The trade publication says: "Set in a riotous 18th Century London and Dublin, the farce follows the drink-sodden and cantankerous Handel who is a forgotten man to all but his whip-smart valet. Worse still, he has lost his inspiration to compose. However, when he overhears the singing of famous actress Susannah Cibber, the composer is moved to write once again and King George II tasks him to create an oratorio to celebrate the new Irish Viceroy in Dublin.
"Yet, when Handel approaches Susannah with the news, he is shocked to learn that not only does she has a fear of singing in public, she's also on the run from her vengeful husband. The motley crew travel to Dublin only to realise that London's gin-soaked alleys are no match for the competing, sectarian politics of Dublin's choirs, the stupidity of English overlords, and the hypocritical morals of the day. Confronted with these odds, Handel has no choice but to defy his critics and keep going. The shown must go on."
Producer Andrew Eaton, who is making the film with Gina Carter, said: "Hallelujah! has been a passion project for me and Gina for a few years. We are thrilled to have Ralph Fiennes and Chris Addison on board and to be partnering with our friends at Altitude on a film we all feel has enormous international and commercial potential."
Further casting details are expected to be revealed about Hallelujah! when production gets underway.