This Shape-shifter is one of the shape-shifters sent to our universe to help Thomas Jerome Newton bring Walternate to our universe. It came along with two unnamed others. This particular shape-shifter, along with the second one survived, however the third one did not survive and was left in a strange egg sack and bisected by the Fringe Division. It turned into a teen man (Dave) after killing him upon first arriving in our universe and accompanied the 2nd shape-shifter to meet with Newton where Newton found out one did not make it.
It changed into a power company worker (David Wu) after killing him as well due to it being the power worker it was able to go to a power box where it planted a strange device it then helped set up more of these devices so it would give Newton enough energy to bring Walternate over. After Newton notices a car pull up and is ordered to change into one of the two police officers which it and its companion due to defend and stall even though it and the other one are killed by Olivia Dunham.
It and the other one succeed as Newton escaped with Walternate who he was able to bring over and escape with him. ("Brown Betty")