A farmer, angry about being foreclosed on, protests by parking his tractor, packed with explosives, right in front of the US Treasury building. Meanwhile, a group of third-graders are brought in by their teacher to find out who stole the class turtle.
After her entanglements with Senator Perrin and the DC Dollhouse, Echo finds herself out in the world-at-large as she struggles to control her multiple memory downloads. Topher discovers the dangers of science that will have devastating effects on the future, while Adelle engages in a power struggle with Harding.
Shirley does the preparations for an upcoming holiday party. Jeff goes up against a school bully after being challenged to a fight.
Mike takes over the responsibility of organizing the Heck family Christmas while Frankie practices for a solo that she is singing at midnight mass. However, she gets jealous when Mike seems to be doing a better job than she ever did. Meanwhile, Frankie and Mike help Brick get over a problem so he can get into the Christmas spirit.
Echo and Bennett have a shocking meeting as Adelle goes head-to-head with the ruthless head of the DC Dollhouse. Topher sees double when he must involve Victor in his espionage. Perrin finds a surprising witness to testify against the Rossum Corporation, but find he may be living in a house of cards.
When Senator Perrin makes his stand against the Rossum Corporation, Echo attempts to stop his expose. Adelle, and Topher begin to see what they are up against in the rival of Washington DC.
Everyone is shocked when a member of the crew is found dead from a gunshot wound. While at first glance it appears to be suicide, the gun is nowhere to be found. The crew is confined to quarters while a search is performed and when the gun shows up in Col. Young’s quarters, he becomes the number one suspect.
Britta dares Jeff to find himself a partner for a double date with Pierce and his new girlfriend. Shirley and Britta help Annie to learn anatomy for a special health fair presentation in school.
After a cargo ship runs aground, the shoreline becomes littered with bodies hosting a giant squid-like creature. The Fringe team descends upon the scene to examine the bodies and discovers that the mysterious organisms are actually giant parasites. As the investigation unfolds, Walter heads back to the lab while Olivia, Peter and Broyles race against time when they realize the case has ties to a threatening organization.
Frankie encounters two perfect siblings and vows to make her children stop fighting and become a loving family. Meanwhile, Aunt Edie makes a costly mistake at the quarry and Mike considers firing her.