The native New Yorkers have both had their share of Hollywood success, "ET" said.
Peet, 33, starred in "Something's Gotta Give" with Jack Nicholson and Woody Allen's "Melinda and Melinda."
Benioff, 35, wrote the Brad Pitt epic "Troy" and Edward Norton's 2005 "25th Hour."
There was no word on whether the couple set a wedding date.
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