The adaptation is in theatre form, and so the traumatic scenes of torture are pretty insane.
Audience members have been reported to physically scream, faint or even throw up while watching some of the scenes. Yiiiikes.
Even cast members have suffered injuries from performing. Olivia herself has broken her tailbone, split her lip and dislocated her rib. Um. Ok.
The Hollywood Reporter said the play, "reaches heights of punishing intensity that will rattle even the most jaded audiences."