Beverley Knight will be making her West End debut as Rachel Marron. Having sold over a million albums in the UK, her hits include "Shoulda Woulda Coulda", "Keep This Fire Burning", "Piece of My Heart", "Gold" and "Greatest Day".
She said today: "To be making my West End theatre debut playing such an iconic role is both somewhat challenging and highly exhilarating".
Tristan Gemmill, who is best known for playing Adam Trueman in Casualty, will play Rachel's bodyguard Frank Farmer. His stage credits include A Streetcar Named Desire, Dangerous Corner and Henry V.
Directed by Thea Sharrock, The Bodyguard is adapted from the hit 1992 film starring Whitney Houston and Kevin Costner and features classic Whitney songs including "One Moment in Time", "Saving All My Love", "I Wanna Dance With Somebody" and "I Will Always Love You".
The Bodyguard won Best Musical at this year's WhatsOnStage Awards.
Booking has been extended at the Adelphi Theatre until 8 March 2014.
Debbie Kurup will continue in the role of Nicki Marron. Also joining the company in September are Richard Lloyd King (Bill Devaney), Stephen Marcus (Tony), Dominic Taylor (Sy Spector), Michael Rouse (Stalker) and Stuart Reid (Ray Court).
Ensemble members are Gareth Andrews, Kimball Armes, Christopher Birch, Hannah Fairclough, Robert Gill, Nicky Griffiths, Ben Harrold, Jamie Hughes-Ward, Alex Jackson, Genesis Lynea, Fergal McGoff, Sara Morley, David O'Mahoney, Stuart Rogers, Kyle Seeley, Danielle Steers, Katy Stredder and Christopher Terry.
Joelle Moses, who has appeared on both The X Factor and The Voice, will understudy Beverley Knight as Rachel.