It’s been 28 years since Disney last followed the Yellow Brick Road – and given the critical and commercial whipping endured by 1985’s Return to Oz, you can hardly blame them for being cautious. Such is the cultural landmark status of MGM’s 1939 The Wizard of Oz that any attempt to adjoin it on screen, however laudable, seems a fool’s errand from the get-go.

The good news is that Sam Raimi’s long, lavish, somewhat lumbering prequel is a more respectful retread than we might have expected. From its engaging black-and-white prologue, introducing James Franco as Oscar, a Kansas conjuror set for a very unexpected journey, to the widened aspect ratio and saturated Technicolor-style palette as he’s carried to Oz by a tornado, Raimi’s film is far more in thrall to the Hollywood classic than the subversive Return to Oz was.

As Oscar is mistakenly embraced by the people of Oz as their leader, charged with settling the battle between good (as represented by Michelle Williams’s wholesome witch Glinda) and evil (vampishly wielded by Rachel Weisz’s Evanora), he’s effectively a smart stand-in for Dorothy, with the film treading a story path as indebted to the original as its explicitly referential production design.

What it lacks, rather like Oscar himself, is any authentic magic: the script’s post-Shrek wisecracks feel out of place, and the over-processed digital landscapes can’t match the beauty of handmade Hollywood artifice. We’re still left decidedly under the rainbow.