As happens nowhere else across the globe, or even in the British Isles, in Scotland the pantomime must go on.

From the smallest community venue to the largest civic theatre, at this time of year Cinderella, Beauty and Snow White, Sinbad, Aladdin and Peter Pan are being gorgeous, beating witches, doing battle and besting one another in feats of derring-do for the attention of the year’s largest and most lucrative theatre audience.

Few stories of professional commitment to the roar of greasepaint and the smell of the crowd, however, rival that of Robert McLeod when he was working for legendary theatre impressarios Howard and Wyndham at the King’s Theatre in Glasgow during the last year of the Second World War. McLeod was possibly the city’s most successful theatrical music director and composer at the time, and his recruitment to the King’s followed a long stint at the smaller Royal Princess’s Theatre in the Gorbals, now Glasgow Citizens’.

Working twice nightly in the orchestra pit was only half of McLeod’s living, however. By day he was a signwriter and commercial painter and decorator, and on the day his heroism made the city’s evening paper, he had fallen from a ladder during his day-job. In great pain and strapped up, he nonetheless made it to his post and conducted that evening’s performances. It was only when he went to hospital later that it was established that he had fractured his spine.

Bobby McLeod’s determination that “the show must go on” made him briefly famous in Glasgow, even if the injury was sufficiently serious to curtail his signwriting work. Now, 65 years later, his music is being heard again thanks to the diligence of researchers at Glasgow University and the careful preservation of some of his work by his daughter-in-law Margaret McLeod, who is now 84.

Staff in the Theatre Studies department at the university, home of the Scottish Theatre Archive, have just assembled a DVD that recaptures the amazing spectacles that graced the stages of Glasgow and Edinburgh in the 1930s, 1940s and 1950s by teaming archive amateur film of productions starring Dave Willis, Harry Gordon and George West with newly recorded music.

One of the successors to those stars of last century, Stanley Baxter, provides a special introduction with his memories of the performers featured in the films.

The disc provides a glimpse from the wings – or one the theatre boxes – of shows on which no expense was spared and which, if successful, could run until April or May of the year following their opening. Shot on silent 16mm film by producer Horace Collins and for stars George West and Harry Gordon, they were intended as a private record only, but had come into the collection of the Scottish Screen Archive. The university’s research team, Sandra McNeil, Paul Maloney and Adrienne Scullion, were able to identify the shows and the stars, but it was a stroke of good fortune and the skill of musicians today that provided them with a soundtrack.

Following his injury, Bobby McLeod had moved from his home in Garnethill in the centre of Glasgow to the south side of the city. It was there that his daughter-in-law had fallen heir to a box of scores for the pantos at the Princess’s, the parts for each instrument in the pit band written out in McLeod’s own hand.

“I couldn’t throw them out, so I’ve carted them from one house to another,” she says. Now living in a retirement flat in Newton Mearns, she mentioned the music at a meeting of her local history group and began the process that would reunite sound and pictures. A fellow member of the group had links to the university and eventually academics from the Pantomime In Scotland project arrived to look at the heirloom in the airing cupboard. In a plot twist that would not be out of place on stage, it turned out that McLeod’s scores were of the same vintage as the archive footage.

The task now was to translate McLeod’s manuscript into music, so Paul Maloney contacted Scottish Opera’s orchestra and concerts director Jay Allen, and asked him to have a look at the scores. With what Allen describes as a “synergy of availability” the orchestra was able to secure the services of musical director Kennedy Aitchison (a man of no small contemporary experience of music for pantomimes and currently in the pit at His Majesty’s in Aberdeen) and recording engineer Philip Hobbs (famed for his work with Linn Records).

“People made sacrifices to make it happen,” says Allen, “and Kennedy had to do a considerable amount of re-arranging so that the music would match the visuals. People are used to hearing a fuller sound than the single strings which most photographs show in pit bands of the time. But the original scores are very interesting and the basic raw material is all there. It is amazing that somebody self-taught produced so much music of that calibre.”

The opera orchestra’s performance of McLeod’s music has been used to score the three films from the Royal Princess’s, shot between 1933 and 1940, as well as most of the DVD’s explanatory introduction about the language and techniques of panto in Scotland. But the other footage, and Stanley Baxter’s reminiscences of the stars who set him of the path to the stage, have music which was improvised specially for the project. It illustrates the unbroken tradition in Scottish pantomime that the two composers and pianists behind the rest of the soundtrack are both as gainfully employed as Kennedy Aitchison in theatres at this time of year.

Dave Anderson has co-written, scored and stars in the show currently running at Oran Mor, a radical revision of Dickens’s A Christmas Carol which won a four-star review from The Herald’s panto queen Mary Brennan this week; and Karen MacIver is musical director of The Snow Queen at Carnegie Hall, Dunfermline.

MacIver’s music not only underscores Baxter’s commentary but also accompanies footage of shows at Edinburgh’s Theatre Royal, Glasgow Pavilion and a spectacular Aladdin at the city’s legendary Alhambra from 1938. Her career includes working as a repetiteur with Scottish Ballet, when she thought she might try her hand at writing for the movies.

“I took a course on writing music for film, and discovered that I wasn’t very good at that, but very good at playing for silent movies,” she says. This anachronistic talent made her ideal for the DVD project but set her very different challenges. While she could normally make up her own themes for the baddy, the goody and the spooky forest, for example, here she was being asked to provide a link with McLeod’s score by reusing his musical ideas.

“It meant memorising parts of his music and then playing along with the images on the screen. In the time available, it was an immense pressure. Then Paul Maloney would suddenly produce another film – the one from the Alhambra – and I’d have to improvise to it, totally blind. And it is like Hollywood, much more grand – the walkdown at the end is huge. Dunfermline, with just six of a cast, seems much more relaxed.”

For most viewers the DVD will be just such an education, a fascinating glimpse of the history behind the type of show so many will enjoy this Christmas. For Margaret McLeod, on the other hand, the experience of attending the recording sessions was much more personal and emotional, hearing once again songs – like I Love Bonnie Dunoon and Bella From Bellahouston – that her husband remembered from his father’s shows and used to revisit at family parties. “I couldn’t believe how wonderful it was hearing all that music come out of the box and come to life again,” she says.

Pantomime In Scotland screens at Glasgow Film Theatre tomorrow, 5.30pm, and Tuesday, 12.45pm. To order the DVD for £18.99, including UK p&p, please call The Herald Film Service on 01634 832789.