Back to the Future legends Michael J. Fox & Christopher Lloyd have taken to their social media pages to tease a mysterious announcement alongside a pair of reunion photos. The importance of the Back to the Future trilogy on the science-fiction genre - and cinema in general - cannot be overstated, with the series remaining as popular today as ever. With the franchise's first outing turning 37 this year, the series celebrated its birthday with a touching reunion between Back to the Future's stars, Fox and Lloyd, at this year's New York Comic Con, much to the joy of the movies legions of fans.

But while Marty McFly and Doc Brown's time-travelling exploits made the Back to the Future franchise one of the biggest film events of its generation, the series has had little continuation since the original trilogy. Despite other '80's sci-fi hits like Ghostbusters receiving numerous reboots, Back to the Future has remained relatively untouched, with the trilogy's director, Robert Zemeckis, even stating that he would stop any attempts to reboot the franchise. Following Fox's retirement from acting, hopes of a Back to the Future continuation were further quashed, seemingly putting the series to bed for the final time.

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But now, Fox and Lloyd have taken to their social media pages to tease a mysterious announcement. The pair posted two photos of themselves together, one, a black and white image of Lloyd and Fox sitting together, the other, Lloyd embracing his long-time friend. Alongside the photos, both actors have posted equally cryptic comments, with Fox saying "Doc and I are up to something heavy" and Lloyd simply putting "Time". Check out the posts below:

What Are Christopher Lloyd & Michael J. Fox Teasing?

Doc and Marty watch the time machine in Back to the Future

While fans will no doubt be clamoring for a reunion between the pair, the real reason for the tease appears to be something entirely different. Following the posts, Lloyd and Fox posted videos teasing what seems to be a new, official Back to the Future merch shop. Many fans online have drawn the conclusion that this new shop is what the pair were teasing, but of course, there could be something else that these cryptic posts are leading to that has yet to be revealed.

The extent of fans' love for the franchise is easy to measure by the reaction to Fox's and Lloyd's posts. Following the photos, Back to the Future fans quickly flooded social media with theories and ideas about just what the pair have been up to, but it looks like a reunion isn't on the cards, at least for now. While no doubt a merch shop might not be what fans were hoping for, having two more photos of Lloyd and Fox back together at least gives Back to the Future fans worldwide something to find joy in.

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Source: Michael J. Fox/Christopher Lloyd