Half past 12 or so, she was leaving the theatre with her mother when she said she'd forgotten something and went back to her dressing room. She didn't come down again.

6 seconds sound clip from the The Picture of Dorian Gray movie soundboard.

You can hear this line at 00:46:06.789 in the Blu-ray version of the movie.

Quote context

[...]

- When I found you'd locked yourself in, I assumed you knew about it.

- There'll be an inquest and you mustn't get mixed up in it.

- They don't know your name at the theatre, I suppose, and if they don't, it's all right.

- Did Sibyl? Tell me everything, Harry.

- It was obviously not an accident. Though I suppose it must be put that way to the public.

- Half past 12 or so, she was leaving the theatre with her mother when she said she'd forgotten something and went back to her dressing room. She didn't come down again.

- They found her lying on the floor. She'd swallowed something. By mistake, they say. She died instantaneously.

- It's tragic, of course, but you mustn't let yourself brood over it. You must learn to see it in its proper perspective.

- For the moment you must put it out of your mind, you must come and dine with me. And afterwards we'll look in at the opera. It's Don Giovanni. Everybody'll be there, and you can come to my sister's box.

- So I have murdered Sibyl Vane. As surely as if I'd cut her throat.

[...]