When the Fringe Team visits Massive Dynamic's assembly of doomsday device, Walter becomes greatly concerned for Peter's well-being, so he turns to Nina for added brain power to understand ... See full summary »



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Episode cast overview, first billed only:
Zach Alpert
Dr. James Falcon
Lars Anderson ...
Lieutenant Pike
Michael Charrois ...
Brett Delaney ...
Agent Goldin
Melissa Demmers ...
Jill Ruiz


When the Fringe Team visits Massive Dynamic's assembly of doomsday device, Walter becomes greatly concerned for Peter's well-being, so he turns to Nina for added brain power to understand the relationship between Peter and the super-weapon. Meanwhile, the discovery of a dead body triggers an intense investigation. Written by Fox Publicity

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Release Date:

28 January 2011 (USA)  »

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Aspect Ratio:

16:9 HD
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Did You Know?


In the opening sequence, the main characters discuss the encrypted computer hard drive that has been accessed since last episode. Walter Bishop explains that his son, Peter, guessed the password: "It was a song lyric. Fauxlivia ruined U2 for all of us." Though it is never revealed in the episode, the U2 song in question must be "One," which has the lines "We're one, but we're not the same." See more »


When the FBI raid Dr. James Falcon's home, every agent extra has serifs on the I's of FBI on their jacket backs, sleeves, and left breasts, but Olivia Dunham and Phillip Broyles are sans-serif. See more »


Fringe Main Title Theme
Written by J.J. Abrams
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User Reviews

Fascinating scientific topics, delicate character development, wowing investigation, unreal dark writing and Do Shapeshifters Dream of Robotic Monkeys?
29 January 2011 | by (France) – See all my reviews

The Firefly effect was intense and heavy on emotions. The bond between Walter Bishop and his son Peter seems unbreakable despite the disastrous impact his saving had on the parallel universe. However in the past episodes their relationship has been unidirectional because it seems Walter is desperate when Peter is quite confident when if he doesn't know what's happening. Even after what happened with Fauxlivia he has always managed to put one foot in from of the other. Don't look back, move forward. He has a goal in his life and won't give up for anything or anyone. Still his connection with Olivia is strong and it's sweet that the writers keep covering it while they work or investigate. It makes it even more authentic and freshen up the episodes with moving moments. However even if Peter is no Parker and definitely not a superhero it seems he has the ability to trigger a very technologically advanced device, the machine. Reciprocity was mostly about developing their interaction. Human-computer is a well known subject because we use smartphones or play video games everyday. But what's their influence on our evolution ? Do we live in symbiosis with the objects we have created ? We're probably as clueless as a clownfish dancing with sea anemones. It's the vicious circle of life and death. Will they win the war ? Could they defend themselves without studying and building the machine ? But asking questions is not enough, almost frustrating, so this installment was also about answering a few of them. The story was actually more twisted than Do Shapeshifters Dream of Electric Sheep?. It wasn't an other silver invasion but something entirely different in the end. It was almost like if they put two writers on the job and convinced them to compete instead of collaborating. One minor issue was made with an awkward revelation that could have been more subtle but overall it was an intriguing and puzzling tour de force ! And as often Walter was a barrel of monkeys. Wait ?!

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