Fringe, Season 2

Walter:
I think I'm starting to understand why the process didn't work. You are different. You're not that frightened child anymore. I thought all we needed was a heightened emotional response from you, but I was wrong. We needed a specific one: fear! And you're not capable of that anymore. Not like she was. What we did to you, you found a way to protect yourself. You channeled your fear into anger, which is why you're so good at your job, but if you want to save those people you have to find your way back to that scared little girl.

Olivia:
And how do we do that?

Walter:
I don't know.

Olivia:
[walks away and finds the room she was frightened in as a child, then sits in the corner]

Peter:
Hey. Is this a part of Walter's test? Are you all right?

Olivia:
No. I'm not afraid of anything anymore.