David Seidler’s play about the stammering King George VI overcoming his handicap with the help of a self-styled Australian speech therapist was first seen on the Edinburgh festival fringe several years ago. The script did the rounds.

Commercial managements did not swamp the now 74 year-old playwright with offers. What happened next, of course, is one of the great show business stories of recent years: a huge movie hit, netting four Oscars and seven Baftas, over $400m taken worldwide, the most successful independent British film of all time.

So this classy touring production, adroitly directed by former RSC supremo Adrian Noble and smartly and glossily designed on a revolving stage by Anthony Ward, is the play of the play, not even the play of the film. Oddly, many of the scenes are cinematically envisioned, and the stage show doesn’t always have the fluency of Tom Hooper’s movie.

Nor, of course, does this version have Colin Firth as Bertie, as the king was more generally known, or Geoffrey Rush as Lionel Logue. But it does have the superb Charles Edwards – who bares his bum, shock horror, before assuming a royal rig-out (“I look like a Christmas tree”) and the vulpine, charismatic Jonathan Hyde in those roles, as well as Emma Fielding as a charming Queen Elisabeth, Daniel Betts as the flippantly debonair abdicating elder brother, Edward VIII, and the ever delightful Charlotte Randle as Logue’s homesick Aussie wife in the couple’s suburban, down-at-heel backwater.

The social embarrassment in the growing friendship between the protagonists is well done. But there’s a hint of another play within this one that is not fully explored: Lionel’s failed acting career, with Logue as an echo of his master’s voice.

Hyde movingly suggests in his too brief audition speeches (as Richard III and Caliban, both vulgar monarchical wannabes) that his failure – “good enough for Perth, not Britain” – is compensated for in Bertie’s triumph on the brink of war.

Noble also injects a spurious Shakespearean dimension into the scenes involving Churchill (a suddenly gargantuan, triple-chinned Ian McNeice), Stanley Baldwin (dapper David Killick), Cosmo Lang, the Archbishop of Canterbury (Michael Feast, archly plotting, all gas and gaiters), and even a short, glowering appearance by an ancient Joss Ackland as the fading King George V.

The show moves on to Nottingham, Bath, Brighton, Richmond (Surrey) and Newcastle. It’s not a great play, but it is very entertaining, and probably deserves a berth in the West End. However, there’s a great conundrum: why would you want to see the play if you’ve recently seen the film, despite the considerable difference in some characters and dramatic emphases?