What better way to celebrate Christmas than to begin filming another mini-masterpiece, God willing? It’s a season of miracles, after all. Many of the presents under my tree had to be opened before Christmas and are taking over the conservatory, which is buried in bundles: swords, battle-axes, spears, masks, hats, fishnets, knee socks, crystal balls, magic wands, witches’ hats, wigs of every colour, false teeth, fake blood, Billy Connolly CDs, bagpipes, corsets, kilts, mini-kilts, sporrans, tams, magicians’ cloaks, tartan, plaid and more tartan . . .

Yes, my latest biographical romp, Bravetart vs the Loch Ness Monster, began filming last Sunday at the stately Walhampton School, a couple of miles up the road from my home in Lymington.

There was a time, back in the middle of the past century, when I was known for my drama-documentaries on the lives of famous dancers such as Isadora Duncan, painters such as John Everett Millais, poets such as Wordsworth and composers such as Debussy. I made almost 50 biographies in all — mostly for the BBC arts programme Monitor, with a film crew of half a dozen or so. There were also a handful of feature films on arty biographical subjects, with crews of about 50.

Half a century later, I’m still at it. I still celebrate inspiring artists, but my current biographical subjects are just as liable to be social misfits whose heroism gallops down backstreets into the land of postmodern chaos. Their creative process may be making art with a paintbrush in their teeth (Revenge of the Elephant Man), raising an army from disparate tribes (Boudica Bites Back), spying (Mystery of Mata Hari), raising the dead (Louse of Usher) or saving one’s family from a bloodthirsty magician (Bravetart). I like to stretch the parameters of expectations — and flirt a little with the edges of bad taste. All in all, I aim for “dangerous beauty”, and I know it when I see it.

The technique of film has changed beyond all recognition since I started. The crews can still be minuscule, as in the early days of Monitor, which encourages an intimate camaraderie, and jobs are often shared: patience is essential when five hours’ work can often result in a mere minute of usable screen time. But the technology has zoomed into sci-fi territory since the early days: film has given way to tape.

And of course the magic green screen has enabled us to put in the background of our choice, from Baghdad to the Baltic, without leaving the studio. All you need for exotic landscapes is a still or moving photograph. In fact, regular readers of this column will be aware that I’ve just finished my latest screen biography, Boudica Bites Back, using green screen and animation in the same way that Sin City, Star Wars and Spider-Man went to town with it.

And so to my current epic. Bravetart is a sassy Scottish prostitute who is played by my (Jill-of-all-trades) wife Elise and is pure invention, with a nod to Mel Gibson. The monsters — both the man (played by myself) and his amphibious ally or “familiar” — are based on real-life characters. The world-famous denizen of the deep is in actuality Nessie, that serpentine creature of myth and legend come to life. For the extravagant claim that she actually exists, I have the word of my one-time cameraman Dick Bush, who saw the monster from a hilltop overlooking the famous loch. Before he had time to reload his camera, the enormous beast had dived beneath the billows. Still, I believe him — Bush was, as they say, a “God-fearing man”.

Which brings us to the second Loch Ness Monster. I’m sure some of you have already guessed that I’m referring to that evil master of black magic, Aleister Crowley — who at one time lived in a sinister castle on the very shores of Loch Ness itself (before Jimmy Page of Led Zeppelin bought it in a moment of rock-star hubris, only to sell it after it proved to be haunted).

But of course Gorsewood Films (my answer to Hollywood) won’t be going to Scotland; no need to when we have Hatchet Pond in the New Forest as a credible stand-in. That plus a dozen kilts and a visit to the Just for Fun joke shop in Southampton should see us through our tale of Highland murder, mists, magic, mischief, mentalism and the martial arts. And as a bonus, the medieval walls of Southampton will adequately provide a replica of Edinburgh Castle.

Bravetart MacDonald, our matter-of-fact hooker with a heart of gold and a brogue as thick as her boot soles, comes from a family of entrepreneurs — all in the flesh trade. Brother and sister arrive as paying guests at Crowley’s castle to participate in a wild haggis hunt, sponsored by Crowley and his trusty henchman MacHaddock (played by Barry Lowe). How the MacDonald siblings end up in a coffin floating down Loch Ness, and Bravetart challenges the magician Crowley to a battle of wits and swordplay — with a bewitched, man-eating haggis joining the fun — are just more thrilling episodes in this bizarre and touching tale.

What is MacHaddock hiding under his kilt? Is Bravetart a common whore or a real-life Highland heroine? Is Crowley pure evil or do his feelings for Nessie and MacHaddock imply a tender side? Will the auld MacDonalds be restored to their clan glory, or will the family end up as fast food for a sea serpent’s snack?

Should auld acquaintance be forgot? Never! Hoots mon and a happy Hogmanay from all at Gorsewood. And some good news: the mini-epic Bravetart vs the Loch Ness Monster will be available by Easter 2009 on a website near you. And may you, like my cast and crew of seven after a hard day’s night, sit down to a pre-Christmas feast with lashings of home-made pizza, mince pies and plenty of plonk. Hame is wherr the hert is.

Explore Film

• Film Reviews

• Trailers

• DVD

• London Film Festival

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010