Jane was performing a plan in the theater. Suddenly, they heard a crashed of thunder and saw rattled outside the window. The light on the stage turned on and off, after few seconds, the power went out on the stage by thunderstorm. So staff apologized them untill untill the light power come back on. это звучит нормально?

"Jane was in a theater, performing a play in front of a live audience. Suddenly, she heard a crash of thunder and saw the windows rattling. The stage light[s] turned on and off. After a few seconds, the power went out on the stage[, due to the thunderstorm]. The staff apologised to her and her audience, and they waited for the light[s] and power to come back on."

What I've put in brackets are things I'm unsure of (such as plurals and extra information).

Feel free to ask any questions, and I hope I've helped!