All of the codes are different for each book so you have to buy a book, or use a code that no one used yet.
IANANDAMYKISSONLIPS1
P66gttnpxp
Club Penguin codes are codes that you can enter online. There are a variety of codes like Card Jitsu Card Codes, Coin Codes, and Book Codes. You can also enter Membership Card Codes if you click the Members tab on the homepage.
Everyone has to buy the book - or you can send a self-addressed, stamped envelope to the address given in the "Help" section of the website (www.the39clues.com). They will send you the cards for Book 1. Agent card codes are free, however, and you can create your own agent card, and share your agent card codes with your friends. For starters, you can add my agent card code "P24R66XMXP", and don't forget to share your own.
P2hcj6hcxp
P4g4mpnnxp
2f6ftnxfx2
P29rp379xp i got it in book 2. Along with some others.
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the card codes are all different, I think but here ar som anyways ! one is 2djpnpm2x4 , that is a thomas secret.
its P3KM69DWXP
P49k47d9xp