The episode follows the Fringe team's investigation into the kidnapping of a young musical prodigy who has become obsessed with finishing one piece of music. Dr. Walter Bishop returns to St. Claire's Hospital in an effort to find the boy's whereabouts.
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This episode's glyphs spell:
Ben Stockton was one of many victims taken by Joanne Ostler to solve her equation, and she used the memories of loved ones taken too early from her victims to coerce them into compliance.
The Observer can be seen while Olivia and Charlie are out looking for Ben Stockton.
In 'In Which We Meet Mr. Jones' Mrs. Loeb handed Olivia a piece of paper hidden in a copy of A Christmas Carol. In 'The Equation', Walter sings Christmas carols over and over to try to jog his memory about the pattern of green-green-green-red lights.
A butterfly is painted on the side of a white trash can in 'The Equation', foreshadowing the fatal, drug-induced butterfly hallucinations seen in 'The Dreamscape'.
- Project 577 - Exploration 5 -
It happens all the time: Newton and Leibnitz inventing calculus. Darwin and Wallace discovering evolution by natural selection. Jevons, Menger, and Walras elucidating marginalism in economics. And yet. Dashiell and the boy -- with nothing in common -- not even working in the same medium -- not even knowing what they were trying to find --
YOU SHOULD HAVE SOLVED IT YOURSELF! IT IS JUST MATHEMATICS, A SIMPLEMATTER OF CALCULATION, NOTHING MORE
Every iteration of the main theme of the composition corresponds to a further expansion of the central function in Dashiell's equation. And with each iteration, he comes a step closer to a closed-form solution. Yet the expansion is infinite, implying a potentially endless composition -- small wonder the boy was obsessed --
EXCUSES. EXCUSES TO RETURN TO WHERE YOU KNOW YOU BELONG.
No! I have the boy now, he is the key, on some level he understands, even if he chafes and bristles -
BECAUSE YOU ARE A BURDEN. AND THE VISITOR CAME AGAIN, DIDN'T HE? ALWAYS PRESSURING YOU FOR THE NUMBERS, THE NUMBERS!
I couldn't stop him, he knows my combination. He bumped my head and I went to bed and I couldn't get up til morning --
ENOUGH RHYMES. THE QUESTION 1S, WHAT HAPPENED WHEN HE LEFT?
It was still there, my box of secrets, a riddle wrapped in a mystery inside an enigma within a lumpy mattress. I should have left it there --
FOR THEM TO TAKE? FOOLISHNESS. IS IT SAFE OR NOT?
I have it now. The box is safe, but my secrets are not. My visitor whispered to me: thank you. No more pearls in this oyster, he said.
Walter's often not too interested in the personal aspects of cases, but this reminds him of what happened to Peter in "Peter".
Peter stayed under false names related to Bishop (Stewart) and Gene (Gene Cowan) in "Northwest Passage", like the villain did in "The Equation".