Marty, you have to understand: this is serious business. - Doc Brown

"Marty, you have to understand: this is serious business."

Doc Brown Truth

More from Doc Brown

"This is heavy."

"There's that word again, 'heavy.' Is there something wrong with the Earth's gravitational pull in the future?"

"Great Scott!"

"If my calculations are correct, when this baby hits eighty-eight miles per hour, you're gonna see some serious shit."

"Lucy, you got some 'splainin' to do!"

"You must always be honest with the people you love."

"Truth always comes out in the end."

"Honesty is always the best policy."