The settings of both the second and third movies in the trilogy are combined to create the second Back to the Future game for the NES. The game was developed by Beam Software, who had no involvement in the first game, this game was also published by LJN.
The game's plot starts similarly to the second movie. In 2015 Biff borrows the DeLoran that Doc and Marty have come to the era in and traveled back to the year 1955 to give himself the Gray's Sports Almanac. He uses this to become incredibly wealthy and powerful. Upon return to 1985 Doc and Mary learn of this and try to set things right.
The plot begins to differ in order to setup the game's scenario, when it's revealed that Biff has also collected quite a few objects from three different time periods (1955, 1985 and 2015) and shifted them around. Marty's goal is to collect the objects and return them to their rightful place in order to advance in the game.
The game begins with Marty on the street level. He must traverse the streets looking for objects and avoiding pitfalls and enemies. The first goal is to find the remote control for the DeLorean which will allow Marty to travel back and fourth between the 3 timelines. In each location the maps are different and the player will need to collect enough fuel in order to travel each time.
Marty locates objects behind hidden doorways. Every door contains a mini room in which Marty must collect stop watches and avoid contact with enemies for a full minute. Once objects are collected Marty must return it to a puzzle room in the correct timeline. Puzzle rooms are found in various drainage pipes and manholes and contain the scrambled name of the object that belongs there. The player must unscramble the word and choose the proper item from their inventory. If correct the room reveals one section of a picture puzzle, otherwise that item is removed from their inventory and returned to the object room in which it was previously located.
A couple interesting features of the time travel game play elements are that Marty may have to preform some action in one of the timelines in order to progress further in the others. However the more often Marty travels back and fourth the more likely he'll run into clones of his past self. Touching a clone causes and instant death.
After all items have been dealt with during the Part 2 section of the game, Part 3 begins much like the end of the second movie and the beginning of the third. Doc has been accidentally sent to 1888, and Marty with the help of 1955's Doc repair the DeLorean to go save him.
The game requires Marty to find 10 items in 1888 and return them to their correct puzzle rooms in order to be able to return to the future and complete the game.
The game was regarded as being a mediocre game, despite the interesting approach, and the huge scope of the game it's biggest fault is it's length. The game features no save or password system and even knowing exactly how to progress through the game it takes quite a few hours to complete.