Back to the Future: The Game

*Missable* Inside the "House of the Future" exhibit, there is a console on the wall that activates a "phone helmet". Using this phone you can make calls and pretend to be someone else. The first thing you must do is go over to the Phone Booth of the Future, near Trixie's info booth. Once inside there, Marty will take note of the phone number.

Now head back to the House of the Future, activate the console, and press the green button. When given the option, chose to call the Phone Booth of the Future's phone number. Trixie will answer and ask who is calling. You must select "Carl Sagan", then end the call. Call back using the same method, but this time select "Kid Tannen". Repeat this process one more time and choose the name "Some Guy". Upon ending this final call, your trophy will unlock.

For more information, refer to the trophy walkthrough under "The Future isn't Written ".