It’s one of those classic What Might Have Been moments. What might have been for young Neil McCormick in August of 1976 when a drummer called Larry Mullen Jr placed a now iconic advert looking for band members on the notice board of Mount Temple Comprehensive School. What might have been had Neil, and not some chap called Paul Hewson, signed up for lead vocal duties on that fateful day. While Ireland’s version of the Fab Four were securing global domination, McCormick and his brother, Ivan, were heading for a one-way ticket to music palookaville.

For future rock critic McCormick, the experiences did at least provide fodder for an acclaimed memoir, 'I was Bono’s Doppelganger', and that memoir has now been adapted for the big screen using a title apparently suggested by Mr Hewson himself.

Filmed mostly in Belfast by Nick Hamm ('The Hole', 'Godsend'), 'Killing Bono' co-stars Ben Barnes and Robert Sheehan as the McCormick brothers supported by Martin McCann channelling his inner Bono.

In adapting the story of these parallel lives for the big screen, many dramatic liberties were inevitably taken. While that’s understandable in terms of dramatic narrative, it does have the effect of diluting the impact of the film. The most interesting parts of the movie are therefore those that involve the eponymous front man, notably the opening sequences at Mount Temple and the closing scenes where Bono and the boys return to Dublin for a triumphant sort of homecoming. In between, we’re left with a ho-hum story about an ambitious band struggling to make their mark on the music scene. It's one we've seen a million times before and it has been done better elsewhere. The key aspect of McCormick’s story is that parallel lives element between the ascending Bono and the struggling McCormick. Take that away and the moviegoing experience is greatly lessened.

On the positive side, Ben Barnes takes his place alongside Cate Blanchett ('Veronica Guerin') in the pantheon of those non Irish actors who have truly nailed the Dublin accent. Robert Sheehan, meanwhile, continues to impress, while recent IFTA winner Martin McCann is convincing in what could have been the unenviable task of portraying one of the most famous men in the world.

A word, too, for the great Pete Postlethwaite, here making his screen swan-song in the role of a camp London landlord (we'll remember him for better projects). Ultimately though, 'Killing Bono', like Neil McCormick’s musical career, is another case of What Might Have Been.

Michael Doherty