So when I left the office I put my rate book on the desk as if I had forgotten it.

5 seconds sound clip from the Double Indemnity movie soundboard.

You can hear this line at 00:47:31 in the DVD version of the movie.

Quote context

[...]

- Only get this, I picked you for the job not because I think you're so darn smart but because I thought you were a shade less dumb than the rest of the outfit.

- Guess I was wrong. You're not smarter, Walter. You're just a little taller.

- Yes, those Fates I was talking about had only been stalling me off.

- Now they had thrown the switch. The gears had meshed. The time for thinking had all run out.

- I wanted my movements accounted for up to the last possible moment.

- So when I left the office I put my rate book on the desk as if I had forgotten it.

- That was part of my alibi.

- From here on, it was a question of following the timetable move by move.

- I got home about 7:00 and drove right into the garage.

- This was another item to establish my alibi.

[...]