To do so, you'll need to talk to everyone in the building, guess where they were at the time of the crime, ask them about possible motives, and of course search for the murder weapon, which is hidden somewhere in the mansion.
Everything in Murder at Masquerade Manor is generated randomly, so it'd be rare to play the same game twice. The murderer, the murder weapon, and the place where the witnesses are located will change each time. You may play one game where the killer is Anonymous and used a knife... and then play again and find out that the guilty one is the Crow and that they used a screwdriver.
Murder at Masquerade Manor is a fun, original game with high replay value. And, it's worth mentioning that the game has outstanding graphics and well-done spoken dialogue.