Former X Factor winner Alex, 25, will take over the role of Rachel Marron on 2 June, after singer Beverley Knight steps down.
Alexandra's exciting news was announced on Twitter this morning by the Bodyguard Musical's official account.
The tweet read: "#TheBodyguardMusical NEWS+ We're proud to announce @Alexandramusic will takeover as Rachel Marron from June 2nd."
Fans have been quick to congratulate Alex on her new job, with one tweeting: "Congratulations Alexandra!! :-) You'll be amazing! Xx."
Alexandra first found fame after winning The X Factor in 2008. She was mentored on the ITV1 show by Cheryl Cole and secured the Christmas No1 with her debut single 'Hallelujah'.
In 2012, Alex took part in a performance from Les Misérables for Children in Need.
Well done, Alex!
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