Walter views Tape 7 in this key Fringe scene. It's courtesy of the show's 11/9/12 episode.
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Where is Walter? That's the question at the center of this key scene from Fringe.
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Fringe Season 5 Episode 6 Quotes

Don't you see Peter? I'm not safe. It's my mind. Ever since the pieces of my brain were re-implanted, it's been changing me back into the man I was before. Bit by bit, I'm losing myself Peter. I'm losing the man that you helped me become.

Walter

Walter: Please son, whatever happens, don't let me go.
Peter: I won't dad, I promise.