The Brown family legally changes their last name from Von Braun to Brown, due to anti-German sentiment during World War I.

Prior to meeting Marty McFly, Emmett lives a largely solitary life, dedicating himself entirely to his research. His unusual behavior and eccentric inventions lead to his isolation within the Hill Valley community.

Emmett gains a strong friendship with a teenager, Marty McFly. He thinks of Marty as his best friend. This is shown when he travels back to 1885 to hide. Emmett only returns to 1985 when he sees that Marty is in danger in 1885 and has to get back to 1985.

Emmett falls in love with school teacher Clara Clayton. Emmett has to make a difficult choice between saving Marty and staying with Clara in 1885. Emmett chooses Clara and remains in 1885.

Emmett marries Clara Clayton and together, they have two sons, Jules and Verne. They continue to pursue scientific endeavors together. The couple live in 1885.

Emmett returns to 1985 briefly with Clara and his sons in a time-traveling steam train, visiting Marty and sharing a fond farewell before continuing their adventures in time.