After completing a scheme you don't just put the scheme card aside, but you have to place it on the Prison Showers card. Depending on where you place the card you complete a specific mission that gives you a benifit or penalty. When completing the final schema you also find one bullet for your gun. You'll need it if you want to wound the snitch so he can't ruin your escape attempt.
The expansion has 2 sides:
A-side: This side is perfect for beginners because it makes the escape easier. Because new players still have to learn the game and make more mistakes the snitch has it easier to win. By using the A-side you compensate for this lack in experience.
B-side: This side is only for experienced players who find it quite easy to escape. The B-side makes the escape more difficult. Good news for the snitch!