Gabriel Byrne has been tapped as the star of HBO's upcoming half-hour drama "In Treatment."

The project, based on the popular and critically acclaimed Israeli series of the same name, centers on a therapist (Byrne) who is calm, smooth, insightful and nonconfrontational with his patients but turns into a testy, self-doubting man full of barely concealed anger when he is a patient seeing his own shrink.

Also cast in the drama, which has received a five-episode order, is Australian newcomer Mia Wasikowska. She will play a gymnast with dreams to go to the Olympics who is receiving psychiatric treatment.

"Treatment" is executive produced by Mark Wahlberg, Hagai Levi and Stephen Levinson.

Co-executive producers are Rodrigo Garcia, who also is directing, and Noa Tishby.

Byrne's upcoming features include "Played" and "Jindabyne," which made their premieres on the festival circuit this year, as well as "Leningrad" and "One Missed Call."

He is repped by Paradigm.