Fans of the 1991 movie will remember Robert Arkins in the central role of manager Jimmy Rabbitte in that comedy but he has been replaced in the new stage show by fellow Dubliner Denis Grindel.
Pony-tailed Andrew Strong sung his heart out in the film but his successor in the new show, another Dub Killian Donnelly (29) made his name in musicals including Phantom of the Opera.
Backing him will be three Dublin girls, all making their West End debuts.
Sarah O'Connor (22) takes the role of Imelda Quirke, played by Angeline Ball in the original movie, in the new production, with northsider Stephanie McKeon (26) cast as fellow singer Natalie Murphy, made famous by Maria Doyle Kennedy.
And feisty Bernie McGloughlin will be brought to life this time around by Jessica Cervi (22).
Veteran Irish stage star Johnny Murphy will be handing his role as 'Joe The Lips' to Londoner Ben Fox.
Star Trek actor Colm Meaney made the role of Jimmy Rabbitte's dad in the original film a tour-de-force and this role will fall to Irish actor Sean Kearns.
Outspan Foster, Glen Hansard in the original film, will be played by UK newcomer Matthew Wycliffe.
The Commitments makes its world premier in London's Palace Theatre on Shaftesbury Avenue on October 8 with previews from September 21.