A BIT of a mixed bag, this comedy rip-off of the overblown, cheesy rock 'n' roll biopic is often a riot but is also guilty of missing the target far too often.

That said, the ever reliable John C Reilly is excellent as the fictitious legendary rocker Dewey Cox but he wasn't given the support he needed to make this one really stand out.

Before he is due to be honoured at a rock 'n' roll awards show, Cox looks back on his troubled life.

When he was a boy, he somehow accidentally managed to slice his more talented brother in half with a sword, but his vow to succeed in life for the both of them has been a particularly difficult one to keep.

Walk Hard takes its often badly timed swipes at the biopic, from The Doors to Ray and, unsurprisingly, given its title, against the more recent Johnny Cash story Walk The Line.

Also parodied along the way are The Beatles, Brian Wilson and even Charlie Manson.

When it's good, Walk Hard is truly hilarious but there aren?t enough comedy gems to keep the momentum going so that it turns into the White Album of modern Hollywood comedies.