Caleb finds himself at the center of A's games on the episode "CTRL:A." Very much to Hanna's chagrin.
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Sorry, Hanna. But your worst nightmare has come true: Caleb has gotten the attention of A
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Pretty Little Liars Season 2 Episode 20 Quotes

Caleb: I've got a hotspot in my pocket.
Hanna: Yeah, I know, but what does that have to do with computers?

I am thinking! This is me thinking! And molting!

Hanna