In Back to the Future 4, the story picks up decades after the original trilogy. Marty McFly (Michael J. Fox), now older and living a quiet life, is visited by an unexpected guest—Tom Holland, playing Marty’s grandson, Jack McFly. Jack stumbles upon Doc Brown’s old journals and learns about the DeLorean, sparking his curiosity about his family’s time-traveling adventures.
When Jack attempts to repair and use the DeLorean, he accidentally triggers a malfunction that sends him back to 1985, where he meets a younger version of his grandfather, Marty. However, this time around, something is different: the timeline is unstable due to an unknown anomaly, creating ripple effects that threaten to erase the entire McFly family from existence.
Marty and Jack must team up across time, racing against the clock to find the source of the anomaly, which turns out to be a rival inventor who has discovered time travel independently. With the help of a surprise return by Doc Brown (Christopher Lloyd), they embark on a wild journey through various historical periods, from the Wild West to a dystopian future, ultimately facing a showdown that will determine the fate of their family and the timeline itself.
