Hollywood can be cruel sometimes.

In 2012 Peter Jackson successfully petitioned MGM to allow him to tell the story of The Hobbit over three films, instead of two.

Back in 1978, at a time when Tolkien’s three-book follow-up The Lord Of The Rings was still considered unfilmable, Ralph Bakshi produced a flawed but ambitious version of the first two books which made six times its production budget, only to be told the planned sequel would never be made.

This has become the frozen, frustrated condition of Bakshi’s The Lord Of The Rings.

It’s defined by the fact that it’s unfinished, a folly that grasps for greatness and falls short by both a hair and a full third act.

With the success of Jackson’s live-action adaptations Bakshi’s film has also been pulled into their orbit, and it’s impossible to watch and not see the triumph it inspired but could not become.

But is it any good?

As all the talk of near-miss masterpieces suggests, the answer is both yes and no.

As a first attempt at whittling Tolkien’s epic into some kind of wieldy shape it’s efficient and sensible, with a selection and omission of scenes that Jackson would broadly follow.

Although Bakshi makes fewer changes to Tolkien’s dialogue, he rides clumsily over several moments that Jackson, with an eye for emotional peaks and a licence to tinker, worked into trilogy highpoints.

Frodo’s despair at realising his task, his understated determination to carry it out, Gandalf’s fall at Moria (“You shall not pass!”) – all are present, but flat and hurried, as if Bakshi is so concerned with getting the big story on screen he forgets about the smaller pieces that make it seem worthwhile.

That’s certainly the case with many of the film’s stylistic choices. In order to cost-effectively recreate massive battle scenes, Bakshi turned to rotoscoping, tracing over rough live-action footage of actors to transplant them onto animated backgrounds.

It’s more successful than Bakshi’s earlier mix of styles in postapocalyptic fantasy Wizards (1977), which treated adult themes with an adolescent cartoonishness, but by the end it’s pushed to the point of incoherence, with barely animated live-action shadows mixing awkwardly with animated figures, resulting in the epic battle of Helm’s Deep looking more like a few shifty extras invading a National Trust site.

It’s a reminder of one of Jackson’s smartest decisions, installing long-time Middle-earth illustrators Alan Lee and John Howe as his lead conceptual artists so his trilogy looked the way fans had been semi-consciously conceiving Tolkien’s world for decades.

Bakshi’s film had no such precedent to fall back on, which makes the handful of occasions where it really nails a design or image all the more of an achievement – its grey, slinking Gollum has become textbook, for instance, while the scene of the Wraiths slashing empty beds at The Prancing Pony is tellingly not in Tolkien’s text but is in Jackson’s film.

For every such achievement, though, there are multiple missteps. Gimli the dwarf is mysteriously just as tall as Legolas throughout, while fire demon Balrog looks like a lion in a Halloween costume.

Those familiar with the story through the books or Jackson’s films will follow events just fine, but others will struggle with a range of things, from the random oscillation of Saruman The White’s name (Aruman in some scenes, Saruman in others), to the comically abrupt voiceover conclusion which wraps things up with Frodo and Sam halfway to Mount Doom.

And that’s where it remains, forever in limbo. Standing alone, Bakshi’s The Lord Of The Rings cannot be considered a success, but it’s unique in being illuminated, for better and worse, by a triumphant successor.

A successor that is probably the film’s greatest legacy – what Bakshi left us, more than anything else, was a desire to see the story it couldn’t finish play out on the big screen.

DVD Extras:

• Featurette