Back to the Future Part II Trailer (1989)

Taking up where the previous film left off, Marty McFly, "Doc" Brown and Jennifer Parker arrive in 2015. Doc tranquilizes Jennifer since she is not necessary for his plan and he believes no one should know too much about the future, explaining that he brought her along since she saw the time machine. Doc explains that Marty's son is about to be approached by Griff Tannen, Biff's grandson, and his gang, who will ask him to take part in a robbery. According to Doc, this event leads to the ruination of the entire McFly family.