The Dinner Party
You walk into the parlor as if nothing happened. You see the next victim. You know it's the thief, you can feel it in your gut. You must not have seen him earlier in the parlor with everyone else. It's definitely him. He was concealing something in his large overcoat and looking around suspiciously. You know you have to act fast before he has time to leave. You walk over to him and ask him if he wants to get some food with you. He agrees and you walk into the dining room. He looks at you very distrustfully and you know he knows your secret. He shifts near a counter and grabs a knife from the knife block. He takes a swing at you but you duck just in time. You grab another knife just in time to jut it right into their abdomen area and he falls to the ground. You rip open his trench coat and you glimpse the file that was stolen. You quickly grab it and sprint as fast you can out of the mansion and into the forest. You have successfully retrieved the stolen file and killed the thief. End of Story.