It's surely not absurd to say that all of us who love film have one special movie from childhood, capable of cutting through the life-hardened exoskeleton of a jaded adult to release the untainted, raw emotion of the four-year-old.

Such a film is Mary Poppins, which celebrated its 40th anniversary this week.

In the tale of the Banks family, 17 Cherry Tree Square, and their short time in the care of Mary Poppins, are combined all the elements required to make a piece of Disney magic.

A flawless cast. Captivating performances across the board from Jane, Michael, George and Winifred, their servants, neighbours and people met along the way.

Such adventure. Tea parties on the ceiling, jumping through pictures to win the Grand National, creating an unprecedented run on the bank (all for tuppence), and up on the rooftops 'tween pavement and stars.

Then the songs. Melodies that bond themselves with the soul. Lyrics that tattoo themselves into the psyche. Jolly Holiday, Spoonful of Sugar and Supercalifragilisticexpialidocious may not offer any great insight into man's condition, but they burst with joy at their own simple existence.

Little matter that it all takes place in one of the most poorly disguised sound stages in Hollywood's history.

And at the film's centre, Mary Poppins herself, with Julie Andrews the very embodiment of the perfect nanny. Enough of a carefree spirit to allow Jane and Michael all the excitement they need, equally ready with suitable discipline when they stray too far across her well-worn line, but not too stern to fail to realise when a soft word will achieve ten times the hard one.

It's an outstanding performance from Andrews. Maria may have defined her career, but it's Mary that gave the future dame her first real taste of fame.

In their 25 Most Magical Movie Moments published last year, Empire nominated 'Feed the Birds' as the one which best represented Mary Poppins. All well and good if this alien moment of saccharine in an otherwise streetwise movie is to your taste.

But for real fans of the film, surely there can be no moment more beautiful than 'Stay Awake' as MP sings her stubborn charges to sleep. Andrews' enchanting voice casts her in the role of siren as she lures her victims onto the down-stuffed rocks to meet their slumbery fate. There are few things more likely to drive me to tears.

But what would Mary Poppins be without her Bert?

Dick van Dyke's turn is beyond fault. His much-criticised cockney accent may grate on some, but in the words of Mr Banks, kindly do not attempt to cloud the issue with facts. His charm, his charisma, his stonethecrowswithapplesandpearsguvnor mugging just serve to make the tale all the more intoxicating.

For while Mary and George Banks may lay down the law, Bert is the true moral compass of the film, and the one with whom the viewer can most easily identify: an object of affection and source of constant attention for Mary Poppins, a comforting shoulder for Jane and Michael following their scares in the back streets of the City, some well-judged advice on parenting for the unreconstructed Victorian Dad Mr Banks.

Bert is our mouthpiece, our guide, our friend.

But of course, this film is about the lady. And what a lady.

Yes, there is something sensual, even sexual, about Mary Poppins. Maybe it's the attraction of a supremely self-confident yet tender woman, but long before the Swedish au pair got her hands on the husbands of Britain, which man could honestly resist the charms of the English nanny with a twinkle in her eye?

Mary Poppins, practically perfectly in every way.

(Apologies for the recent silence - I've not been feeling myself).