The repercussions of Peter’s (Joshua Jackson) return to Fringe are apparent, but just how much is his presence impacting the world around him? And is there anything that can be done to fix it?

In tonight’s episode, entitled “Wallflower,” an invisible force is proven to be behind the death of an innocent man. After his dead body begins to take on the appearance of a ghost, Walter (John Noble) and company jump on the case.

While attempting to search for what’s behind this mysterious event, the Fringe team stumbles upon other occurrences of this invisible force, which have resulted in additional deaths. When all signs point to a single person behind these preternatural slayings, they soon find out that it’s an unknown genetic disorder that’s driving him to kill.

Unfortunately, while everyone is focused on the case of the ghostly non-ghost, Olivia (Anna Torv) suddenly begins to suffer from migraines. While there may be several reasons for her cranial pain, all logical signs point to her memories of Peter as the cause.

But how do you solve a problem that’s cause by a man who shouldn’t exist? And, more importantly, how do you make sure it doesn’t happen again?

If you’re posting comments here, assume that anyone in the conversation has seen the episode – if you haven’t seen the episode, I would recommend you don’t read these comments here until you have. You’ve been warned.

Discuss away!

Fringe airs Fridays @9pm on Fox

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