The Adventure Begins.

You wake up in bed finding that everyone is gone and your door is locked in from the inside. You see lots of blood on the walls and floor, and multiple weapons and food on the desk next to you with a note attached to them; "We're going to Washington. If you wake up, try to get there." The only thing you remember right now is that you were in a blast and got injured. Wind blows in from the open window and you think you hear a faint shouting. You slowly walk to the window to see what is happening and you are shocked. Everything is in ruins. Fires are everywhere and buildings look demolished. You stare on at the sudden change until you notice somebody running. Then the full shock comes. You see what can only be a zombie chasing a man. You look at the gun and realize you can save him.

Zombie
Save the man. Save your ammo.