He'll replace Ian Barford. Best known for his portrayal of Detective Roland "Prez" Pryzbylewski on HBO's "The Wire," True-Frost's New York credits include Buried Child, Philadelphia, Here I Come!, The Rivals and The Grapes of Wrath. He has been a Steppenwolf Theatre Company ensemble member since 1989.

His credits also include The Homecoming, David Copperfield, Side Man, The Pillowman, The Playboy of the Western World, The Grapes of Wrath and Killers (Joseph Jefferson Award). His film credits include "Diminished Capacity," "Slippery Slope," "Off the Map," "Affliction," "Singles," "The Hudsucker Proxy" and "Far Harbor."

Directed by Anna D. Shapiro, August: Osage County "is the explosively funny comedy-drama focusing on the Weston family following the disappearance of the family's patriarch."

The play has been nominated for a batch of 2008 Tony Awards, including Best Play.

August: Osage County performs at the Music Box Theatre (239 West 45th Street) Tuesday-Friday at 7:30 PM, matinees on Wednesday and Saturdays at 2 PM, Saturdays at 8 PM and Sundays at 3 PM.

Tickets can be purchased at Telecharge.com, or by calling (212) 239-6200 or (800) 432-7250.