She is best known for her roles in the television series The Sopranos (2001), Fringe (2009-2010), Bad Teacher (2014), I'm Dying Up Here (2017), and Monsters: The Lyle and Erik Menendez Story (2024).

[5] She attended Buckingham Browne & Nichols, a private school in Cambridge, Massachusetts (Class of 2001), and Trinity College, Hartford, Connecticut.

[citation needed] During a June 29, 2017, CBS late-night interview with Stephen Colbert, promoting I'm Dying Up Here, she mentioned she went to a prom with future congressman Joe Kennedy III.

In 2010, she appeared in the play Trust at the off-Broadway Second Stage theatre company with Sutton Foster, Zach Braff, and Bobby Cannavale.

[8] Graynor starred on Broadway opposite Cheyenne Jackson, Henry Winkler, and Alicia Silverstone in David West Read's play The Performers, which opened November 2012 at the Longacre Theatre.