S4:E5 Dirty Harry
Original Air Date: Oct 25, 2009
Dexter is inspired to investigate the Trinity Killer on his own, while Debra blames herself for an event that was out of her control, and Rita realizes how little she knows her husband after discovering one of his secrets.
"Dexter finds himself identifying with a killer again - this time because they're both family men hiding their murderous impulses under a veneer of normalcy."
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