Jordan Chase enters the picture on the episode "Circle Us." He plays a motivational speaker. A very shady one, that is.
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Dexter Season 5 Episode 7 Quotes

That's either a saint or the most boring action figure I've ever seen.

Dexter

Sometimes partners find us, and as much as we try to push them away, they work their way into our lives, regardless - until we finally realize how much we need them.

Dexter