She was walking on, [was over]

The protagonist, Philip moved in with his uncle Mr. Carey, the Vicar of Blackstable after his mother's death.
He goes to the medical school St. Luke's in London.
He fell for the waitress Mildred. He went out with her, but she didn't like him, and she got married to g German.
After she was dumped, she came to Philip's apartment.
Norah is Philip's best friend and lover. He have came over Norah's for tea everyday.

............................................
She went away and he found that she had been there for two hours. He was extraordinarily happy.
"Poor thing, poor thing," he murmured to himself, his heart glowing with a greater love than he had ever felt before.
He never thought of Norah at all till about eight o'clock a telegram came. He knew before opening it that it was from her.
Is anything the matter? Norah.
He did not know what to do nor what to answer. He could fetch her after the play, in which she was walking on, was over and stroll home with her as he sometimes did; but his whole soul revolted against the idea of seeing her that evening. He thought of writing to her, but he could not bring himself to address her as usual, dearest Norah. He made up his mind to telegraph.
[Of Human Bondage by Somerset Maugham]
I'd like to know what "was over" means.
Thank you in advance for your help.