Zach Grenier is an American film, television and stage actor.
Grenier was born in Englewood, New Jersey. He attended Pioneer High School in Ann Arbor, Michigan.
He appeared in the first season of the television show 24 as Carl Webb, was in Deadwood, and on several episodes of Law & Order. He currently plays David Lee, a senior attorney in The Good Wife. On film he played Edward Norton's boss in Fight Club and Mel Nicolai in Zodiac, both David Fincher films. He also appeared in the movie Twister as Eddie, Dr. Jonas Miller's assistant. He also plays one of the Callahan Auto Parts associates in Tommy Boy. He appeared in Donnie Brasco, as a marriage therapist. He played a role of Professor Cardiff in an 2006 horror film Pulse.
In 2009, he appeared on Broadway opposite Jane Fonda in 33 Variations, earning him a Tony Award nomination.