Breaking and Entering Trophy
Breaking and Entering
Find a way into the Research Lab
This is story related and cannot be missed.
Shortly after beginning level 4 you will have an objective to disable the power. After you have done this follow up the nearby stairs and enter the room with lots of computers in. In here there will be a guard, you will have to take the head of the guard to continue. Simply take his head & use it on the retinal scanner, in between the cut-scene that follows you will get the trophy.