As ill-judged Star Wars ideas go, it's up there with the purple lightsaber – though might have some way to go before it can compete with Jar Jar Binks. Photographs have emerged for the first time of the monkey in a mask which George Lucas et al once hoped might play diminutive Jedi master Yoda.

The story of how the unnamed simian was screen-tested for the role of the galaxy's greatest backwards-talking warrior - he was even taught to hold Yoda's cane - has long been part of Star Wars mythos. It was documented in JW Rinzler's 2010 book The Making of Star Wars: The Empire Strikes Back. But it is believed the shots of the monkey on set have not previously hit the public domain.

Lucas apparently felt the combination of animatronics and puppetry eventually adopted for Yoda (with legendary Muppeteer Frank Oz providing both movements and voice) would not be realistic enough to convince film-goers. But the monkey alternative was ultimately abandoned when it emerged the simian in question preferred pulling his mask off and waving it about to actual acting. Try as they might, animal handlers could not train their new cast member, and Oz got his chance instead, with the results eventually making celluloid history.

The pictures were first tweeted by Star Wars fan Will McCrabb.

Meanwhile it has emerged that Star Wars acolytes who cannot wait until Christmas 2015 to see the space opera hit the big screen once again may have another option to catch some of their favourite characters. The forthcoming Lego Movie - due out in February- will reportedly feature tiny plastic versions of several of the best known figures from Lucas's original trilogy.

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