What's the code to the safe under Abbott's bedside table?

1. Do you remember that cryptic note you found in the puzzle box?

2. Try and figure out what the names have in common.

3. They're all knights, aren't they?

4. Four of them. Where can you find four knights?

5. If you're stuck, you can always ask people about it.

6. Ask Barnet about the note.

7. Lucky that there's a chessboard right on the table over the safe.

8. The knights are all in strange positions. It probably means something.

9. If you need more help, a book is always a valuable source of information.

10. Go take Dr. Dominick's book from the table he shares with Barnet.

11. Have a look at it. It's all about games.

(PARTIAL SOLUTION FOLLOWS)

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11. Now you know the exact coordinates each knight's position corresponds to.

12. The letters spell out the code. The numbers show the letters' order.

(SOLUTION FOLLOWS)

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13. The code is BADE, or 2-2-3-3.