Shenkman was born to a Jewish family[1] in New York City, the son of Katherine, who was an associate at a law firm, and Shepard A. Sheinkman, who worked for a consulting company.

[4] He also began working in theatre, portraying Louis Ironson in Tony Kushner's play Angels in America at San Francisco's American Conservatory Theater.

Throughout the 1990s, Shenkman combined work in off-Broadway productions in New York with small roles in films such as Eraser (1996), The Siege (1998), π (1998), and Jesus' Son (1999), Chasing Sleep (2000), and Requiem for a Dream (2000).

After the release of HBO's Angels in America miniseries, he returned to Manhattan Theatre club in 2004 in Sight Unseen opposite Laura Linney.

[citation needed] He also acted on TV as a series regular in the 2008 Julianna Margulies legal drama Canterbury's Law on Fox, and in recurring roles on Grey's Anatomy, Burn Notice, Damages, Drop Dead Diva, and FX's Lights Out.