SIGNAL & NOISE

A cryptanalysis campaign on a bakelite desk of working instruments. Twenty-four intercepted messages, six families of cipher, and a frequency counter, substitution board, Vigenere slide with a Kasiski drum, transposition grid, three-rotor KESTREL machine and crib bench to break them with. Every slip is a real, solvable puzzle with one deterministic answer: read the day's brief, take the promised crib, form a hypothesis and watch the clarity meter rise as the plaintext comes out of the noise. No trivia, no luck, no hidden information — only deduction, and a green lamp over the work.