If there is the faintest breath of life, it will cloud the mirror. You see?

10 seconds sound clip from the Isle of the Dead (1945) movie soundboard.

You can hear this line at 00:27:43.877 in the Blu-ray version of the movie.

Quote context

[...]

- It's Mrs. St. Aubyn's affair, and of no concern to you.

- Please listen to me. I've got to make you understand. He's not dead. No. I won't believe it. He's not dead.

- But Dr. Drossos is a Medical Officer.

- I don't care who he is. He doesn't know. He can't tell.

- I'll make any tests you want.

- Look. He's not dead!

- If there is the faintest breath of life, it will cloud the mirror. You see?

- The breath can stop. The heart can stop. It still doesn't mean death. Men have lived...

- Quite right. In cataleptic trance, a man may live for days with no visible sign of life. The breath suspended, the heartbeat stilled. But this man is dead.

- What difference does it make? Uncovered or covered, the eyes see no more.

- Looks all right. It'll give us all something to do.

[...]