Hired Assasin

You grab your revolver from the nightstand in your room. You normally keep a revolver hidden throughout the apartment you never know when a pissed off client is gonna come lookin.

You head for her room and gently slide open her door just a crack. As you look inside, you see him. He is holding her at gunpoint with agun to her head.
You notice the window is open. He must have crawled in thru the fire-escape.She must have unlocked the window.

You bust in the door,"Let her go and I let you live for the night" you say.

"I'll kill her!" the goon replies.

You have your gunpointed right at his head as he has his gun pointed at her head.

You have 2 choices: