In her introduction to this 40th Anniversary DVD, Julie Andrews calls The Sound Of Music the "most watched musical" in history. While fans of The Wizard Of Oz may balk, the global impact of this all-singing all-dancing fable of family values is undeniable. Despite a jollied up portrait of Nazi incursion, director Robert Wise erred just the right side of that fine line between the sublime and ridiculous.

Climb Ev'ry Mountain

"It's like a breath of fresh air every time you see it," coos Ms Andrews in an hour-long documentary My Favourite Things. Instead of a meticulous blow-by-blow account of development and production, the cast and crew offer their individual recollections. Above all everyone remembers the real Maria Von Trapp, especially Wise who says, "She was kind of bossy and I'm the director of the thing so I didn't like that about her." Meanwhile she noted of Christopher Plummer, "You are even more handsome than my husband," but the actor went from flattered to freaked out as the "gushing baroness" wouldn't leave him alone.

Andrews and Plummer share more memories in a fireside featurette and their chemistry is as sparkling as ever. "It wasn't difficult to fall in love," says the silver-tongued Plummer, "Not with you." He even makes the embarrassing admission of turning up to rehearsals in ballet tights, which left his colleagues amusingly nonplussed. It's no wonder he found the cold Austrian nights so hard going...

Charmian Carr, who played Liesel Von Trapp, takes us on a tour of the film's locations in Salzburg. In real-life the Von Trapp's lived in a modest country villa, but the mansion represented in the film was the combination of two grand palaces - the Frohnburg and Leopoldskron. It made shooting some of the exterior dialogue very tricky, with one half of a conversation happening at an entirely different setting from the other half of a conversation.

Caught In A Trapp

The child actors who played the Von Trapp children are, of course, adults now, but babble together excitedly for a cosy, reunion featurette. The darker-haired children were stunned to be offered the film because they didn't have the stereotypical Aryan features, but "hair and teeth" did eventually pose a problem. Over the course of the shoot, the older children got taller and the younger ones lost teeth, all of which proved a nightmare for the continuity department! Elsewhere there's rarely seen footage of Mia Farrow testing for the part of Liesel.

The real story of the Von Trapp family is predictably less glossy in the documentary Harmony & Discord. Perhaps the most glaring discrepancy is that Maria Von Trapp was not in love with her husband when she married him. In a letter she plainly stated, "I didn't love him, I loved the children." Johannes Von Trapp - the product of this marriage - takes part in the two documentaries and a patchwork commentary for a beautifully restored main feature. Thankfully Andrews and Plummer keep the track light with great behind-the-scenes anecdotes, eg the famous opening scene in the Austrian mountains took hours to shoot because the downdraft from the helicopter kept knocking Andrews over!

Robert Wise hosts an alternative track, which presents all of the music without vocals or dialogue. He has a very sharp recall of the challenges faced by the production, from unscripted rain to unending choices about the placement of each song. Except for brief discussion in My Favourite Things, it's surprising that there isn't more focus on the Rogers & Hammerstein soundtrack. However, there is a karaoke track for those who've memorised the numbers and a featurette on this recent sing-along phenomenon. Without a doubt, this Collector's Edition DVD will have fans flying high as the Alpine peaks.

EXTRA FEATURES

Disc One

Disc Two - Only available as part of the collector's edition