Back to the Future
Robert Zemeckis' much-loved 80s hit time travel sci-fi film, starring Michael J. Fox as teenager Marty McFly, who through his friendship with eccentric scientist and inventor Doc Emmett Brown (Christopher Lloyd), finds himself not in 1985, but 1955. To make things worse, his presence may prevent his parents from getting together. Of course, Marty must fix this and get Back.... To The Future!
The 1985 smash led to a further two films being made, taking Marty further back and forward in time. Great Scott!