You are running in a building from a group of zombies chasing you. Your lover as well as your best friend has been bitten by a zombie, and now you are alone and in a bad state

You accidentally trip when you are about to turn. A zombie manages to be above you, you immediately quickly hold his neck with the baseball bat you carry. Until suddenly the zombie that was above your body was shot by a mysterious man. He grabs you and takes you running somewhere

"We have to get out of here."