HERCULES on the big screen is pretty much one long tradition of fun. Often camp and cheesy at times, sure - but in the best way; many a movie lover’s childhood has been enriched by a pungent slice of Steve Reeves/young Arnold Schwarzenegger magic in there somewhere, and a continuation of the line is rarely a bad idea.

Better yet, the 2014 iteration of the Greek myth has Brett Ratner at its helm - whatever you think of the director-for-hire, fun is the one thing you'd think you could be assured of. But something, somewhere has gone slightly astray. Sure, the levity is partly there... a bit... but in worrying about the fromage factor, Ratner and/or Paramount keep steering back and forth between that lightness and a more po-faced, 300-esque tone, messing with the storytelling consistency to a highly noticeable degree.

Based on Steve Moore’s comic book variation of the tale, we're introduced to a younger Hercules (Dwayne Johnson – who else?), before he has completed his ‘twelve labours’, where it quickly establishes a great premise: the demi-god wasn’t such at all, just an exceptionally large human who yes, was very adept at combat, but who also cannily surrounded himself with a band of merry men (and one woman - an Amazon, naturally) who were equally good at fighting and - crucially - illusion, and more than happy to let themselves be written out of the myth in exchange for healthy, regular payment.

These compadres turn out to be not only of utmost importance to The Big Man, but to the movie itself, particularly a wise-cracking Rufus Sewell and vaguely mystic Ian McShane - they bring the fun, and are absolutely invaluable for it. They're aided a lively Reece Ritchie as Herc’s nephew – not a fighter, but an orator (ooer) in charge of the myth-making and storytelling. The gang is rounded out by the aforementioned arrow-slinging Amazon Atalanta (Ingrid Bolsø Berdal), and a berserker (Askell Hennie).

Herc and co. are summoned to the aid of King Cotys of Thrace (John Hurt also doing a lot of the movie’s heavy lifting), whose homeland is being marauded by Rhesus (Tobias Santelmann), so needs his few remaining subjects trained into fine soldiers. The mercenaries agree, and we’re set on an adventure about believing in yourself in the face of overwhelming odds, and forging your own myth by simple virtue of unrelenting self-belief.

Which is fine, but for frequent detours into the literal Greek tragedy of Hercules’ backstory. Either of these two moods would be fine apart, but Ratner is constantly trying to reconcile the tone, and never does the twain completely, or comfortably, meet.

Ironically for a movie about a confused child of two planes of existence, Paramount’s HERCULES wants the best of both worlds – to be light and jaunty like its predecessors while still carrying weighty backstory; to maintain that ‘family’ vibe of a JASON & THE ARGONAUTS while including some quite brutally realistic violence; to inhabit a world that is equal parts Christopher Nolan and Roland Emmerich – something which not even the might of Johnson can hold together for long.

Behind the camera it's also a mixed bag. Dante Spinotti’s cinematography looks great in daylight (and the use of many actual human extras in the battle scenes is to be commended), but the torch-lit interiors – at least with 3D glasses on – have that tedious, murky appearance, while Fernando Velázquez’s score, like so many of 2014’s big films, fails to make any kind of memorable impression, let alone raise the film.

What they have got right, of course, is the casting of Johnson in the role he was bound to get around to eventually. Following in the footsteps of Reeves and Schwarzenegger, the Samoan royal is such an obvious and perfect fit for the Hercules, the question was never one of him being worthy of it, but whether it would be worthy of him. Is it? Almost.