A teenager with the power to control minds can be a very terrible thing, as Peter Bishop finds out firsthand this week.

As Walter and the rest of the team race to save him, will Peter's mind be strong enough to fight off the urges to kill? And is this young man a vicious mutant or the by-product of an evil science experiment? Read our recap of "Of Human Action" for the answers and simply read below for our take on the episode...

What Worked: Walter's Foil: A Tale of Two Fathers
It is apparent from the get-go that Dr. Carson is not going to win father of the year. He claims to not know much about his own son and seems to value his work at Massive Dynamic more than his role as Tyler's dad. Tyler reveals that he is angry at his father. We know that Walter, on the other hand, loves Peter with all his heart. And his brain, too, as the genius, distraught at the idea of losing his son, says he can't function without Peter. Having the cold Dr. Carson serving as Walter's foil helped to drive home the true power of the relationship between the Bishops.

Tin Foil: A Tale of Two Hats
While working on a way to stop Tyler's mind control within the walls of Massive Dynamic, Walter and Astrid don tin foil hats. Agent Dunham, seeing the gear, hopes that they've developed more than simple headgear to stop Tyler. However, Walter points out that the tinfoil is not meant to stop Tyler but Massive Dynamic, which he thinks is trying to steal his thoughts. Hey, we wouldn't put anything past the creepy company.

What Really, Really Worked: A Tale of Two Sons
When faced with the thought of losing Peter to Tyler's mind control, Walter mutters "I can't lose him again." It seems that only Nina Sharp picks up on this, but then again, outside of William Bell and Walter Bishop, there is no one who understands the two alternate universes more than Ms. Sharp. We are left to wonder what the scheming Ms. Sharp will do with this nugget of information.

Communications Upgrade
We've always had a hunch that Nina Sharp is not as benevolent as she seems. She may give the appearance that she is trying to help Agent Dunham, but she also has her own agenda. As the episode ends, we see her communicating with William Bell - via an old-timey computer, a significant upgrade over The Agent Formerly Known As Charlie Francis's typewriter - and letting him know that their mind control experiments were a complete success. We are left to wonder just what Nina Sharp is: friend or foe.

Among our favorite Fringe quotes from the episode:

Walter: All commands will come through the headphones. Once you're given the order to put on the headphones, do not remove them under any circumstances. If you do, you may die a gruesome and horrible death. Thank you for your attention and have a nice day. | permalink

Walter: This is exciting. You think the FBI will ever give me a gun? | permalink

Astrid: Chicken. You serious?
Walter: Just a hypothesis. What do you think, more like pork?
Astrid: Truthfully, I don't really spend a lot of time thinking about what human brains would taste like.
Walter: Then why did you ask? | permalink

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.