People think there could be a Back to the Future 4 coming soon

Christopher Lloyd is sending social media into overdrive thanks to a series of cryptic posts that some people think is a tease of a Back to the Future reunion.

Lloyd, who plays the iconic zany scientist Dr Emmet Brown in the Back to the Future films, shared a picture of him standing close with his co-star in the films, Michael J. Fox.

The image was shared with the caption: "Time."

In another tweet, Lloyd said: "If my calculations are correct, when this news hits 88 miles per hour…you’re gonna see some serious s**t (on Instagram)."

In an Instagram post of another photo of he and Fox, Lloyd wrote: "Wait, don't say anything yet, Michael J Fox. We’ve still got time."

He added: "I can’t say yet, but the future holds something very special for you…stay tuned."

Lloyd has also been tweeting emojis of clocks, quotes from the three movies, and repeated references to time and 'Great Scott', his catchphrase in the films.

Social media has blown up as a result, with many fans sharing their excitement on Twitter.

One user said: "It can't be Back to the Future 4 after all this time?"

Another added: "Wait so is Back to the Future 4 actually happening"

A third piped up with: "Gonna lose my mind if they make a Back to the Future 4."

Some fans, however, were not so keen.

One user just repeated the sentence 'please don’t be a Back to the Future remake' until they ran out of characters.

Another said: "Are they just openly teasing Back To The Future 4? I just find that hard to believe."

A third added: "Please let this just be an announcement that he’s a navigation voice option for the new electric DeLorean and not a Back to the Future Part 4."

Lloyd's blatant teasing on social media came one month after the dynamic duo brought fans to tears with a reunion at New York Comic Con.

After he was joined by Lloyd, the pair hugged it out before taking to the couch to respond to fans’ questions.

Posting the footage on Facebook, fan Carl Mitchell wrote: "Back To The Future reunion at New York Comic Con. So sad to see Michael J Fox like this but he's such a fighter. That hug with Christopher Lloyd was so emotional.”

The clip soon went viral as it was re-shared across social media, with one person saying on Twitter: "I’m not crying, you’re crying."