The JJ Abrams project stars Jim Caviezel as a CIA agent who teams up with a mysterious businessman, played by Michael Emerson, to catch criminals in New York.
TV Guide reports that Zea has now signed up to play a district attorney who may be putting her life at risk by investigating a homicide.
Zea plays Winona in Justified and has previously appeared in shows such as Hung, The Defenders, Dirty Sexy Money and The Shield.
Person Of Interest, which will also star Kevin Chapman and Taraji P. Henson, is in contention for CBS's 2011-2012 season.
The project has been penned by The Dark Knight scribe Jonah Nolan.
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