The suspect will be charged with murder, attempted murder, armed robbery and possession of an unlicensed firearm.
During the theatre attack, a Zimbabwean band was playing on stage.
"I was tired so I moved my couch to a room further from the theatre as I was waiting for the show to end," Mkhwanazi said yesterday.
"A while after I moved I heard gunshots. [I thought] it was on the next street because the theatre is the safest place in Hillbrow," he said. "Eventually, I realised there were screams and then silence. I came out. I couldn't believe it."
Eyewitnesses described how a man got on stage and allegedly threatened that things would get bad if his missing cellphone was not returned. The audience laughed when he mentioned the phone may only be worth about R50 but it meant a lot to him. At that point he allegedly produced a gun and started shooting.
At the exact spot where Mkhwanazi's couch had been earlier were two bullet holes in the wall - a chilling sight that made him realise he was lucky to be alive.
Patrons and staff discovered that one person had been killed only when a man, who was seated, failed to get up after the fracas.
Gerard Bester, director of the theatre, said said that closing the theatre was not an option.