The second person theory is the theory that, in almost all circumstances, the perpetrator in a crime based television show is the second introduced character in the episode. They are typically introduced after or just prior to the first lead and suspect. Holds true at least 90% of the time.
Refer to any episode of any crime show ever.

<dude 1> "They did it."
<dude 2> "What, how do you know that?"
<dude 1> "Second-Person Theory.
by Extracting December 01, 2013
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