Answer: Secret Code #20

The secret message says:

BEEP BOOP

The shift was 3.

The secret note decoded: BEEP BOOP
The note, decoded.

Letter by letter

Secret letterEHRS
Real letterBEOP

Decode it with Python

This program does the decoding for you. Change the secret and the shift to crack other messages!

secret = "EHHS ERRS"
shift = 3
message = ""

for letter in secret:
    if letter.isalpha():
        number = (ord(letter) - ord("A") - shift) % 26
        message = message + chr(number + ord("A"))
    else:
        message = message + letter

print(message)

When you run it, it prints:

BEEP BOOP

Did you know? Shift codes are very old. A Roman writer called Suetonius said that Julius Caesar wrote secret letters by shifting the alphabet by three. That’s why it’s often called the Caesar cipher.