Many films including The Exorcist and Blade Runner have multiple versions

Some filmmakers like to tinker repeatedly, creating multiple versions of movies, like Francis Coppola with Apocalypse Now, George Lucas with Star Wars and Ridley Scott with Blade Runner (where a certain dream provided an important clue). Whether or not different versions - or particular scenes - are better or worse is arguable, but for fans the comparisons can be fascinating and important to film history (even if Lucas, annoyingly, doesn't want his original Star Wars films to be available).

Sometimes a film is released in a new version like The Exorcist. "The Version You've Never Seen" features footage writer-producer William Peter Blatty had wanted in the original and the director, a more mellow William Friedkin, obliged (and tweaked the special effects). The film had appeared in altered form on TV with less graphic shots substituted and milder language inserted: this creates yet another version.

The first two Godfather movies got re-edited into a chronological saga for television but although deleted scenes from the two films have been released, that TV version hasn't.

And some revisions can be shorter than the original: Blake Edwards' final cut of Darling Lili (1969) made two decades after its initial release had nearly half an hour excised.

Sometimes long-ago deleted scenes get rediscovered, like the extended Scarecrow dance in The Wizard of Oz. While it hasn't been reinserted in the movie, the scene is enjoyable in its own right even if it doesn't add anything to the story. But nobody has found the Jitterbug scene in which Dorothy and company are given the "jitters" by mysterious insects. Only some home movies shot by composer Harold Arlen on the set survive though the soundtrack was preserved. Its omission makes the Wicked Witch of the West's line "I've sent a little insect along to take the fight out of them" puzzling. Other tantalising omissions include Hickory's "heart" speech to Dorothy (foreshadowing his Oz appearance as the Tin Man) have been lost. It would be fantastic if they turned up in a storage tin somewhere.

It's A Mad Mad Mad Mad World and Spartacus are two films where multiple releases led to various excisions for length or censorship reasons. Spartacus's restoration included the more violent battle footage and the notorious "snails and oysters" seduction scene. Tony Curtis returned to revoice his dialogue but Anthony Hopkins has to imitate the deceased Laurence Olivier. In one case, the soundtrack of a character's suicide had survived but not the visuals.

World, the general release version of which was a bit over two-and-a-half hours, was expanded to run over three hours as it had originally. While the idea of a comedy of that length is daunting - and the film itself is mostly an excuse for a parade of comedy cameos - it's always good to see movies as they originally appeared (are you reading this, Mr Lucas?) as well as in rejigged, re-edited versions.

Similarly, the 1954 film A Star is Born was also cut down to two-and-a-half hours (the shorter running time allowed an extra showing per day) and was restored nearly 30 years later, though significant portions of its three-hour duration had to be represented by stills with soundtrack (as happened with World).

And Lost Horizon (1937), which premiered at 132 minutes, was cut within months to a 118-minute general release version and eventually, amazingly, a 92-minute TV version (Forty minutes is nearly a third of the length of Lost Horizon - did it still make sense?!).

Restorations in the 1980s, 1990s and in 2016 added more footage (sometimes still photos with soundtrack, as with Star) getting the film as close to the original as we are likely to have.

Willy Wonka and the Chocolate Factory originally had a scene director Mel Stuart loved among the vignettes where people seek golden tickets. In it, an explorer climbs a mountain to ask a guru the meaning of life. The guru asks the explorer for a Wonka bar and when he opens it and finds no ticket, he answers., "Life is a disappointment." It got little response and Stuart asked a psychologist friend why. His friend replied, "You don't understand, Mel. For a great many people, life is a disappointment."

This, too, seems to have been lost.

The search through archives, garages, sheds and other places will, we can only hope, continue, so the preservation and restoration of the world's cinematic heritage continues - before it's too late.