When Lieutenant Kitty Spinoza and her platoon are thrown into the hot dark aluminum prison, they have a simple cypher ready within hours: boring sentences, their word order changed to mean “cell checks tonight” or “southwest corner.” The laundry room becomes a post office. As they end up in solitary, one by one, they write a better tapping code than Morse.

When they disassemble the prison and it’s all a hoax, an experiment, the Major congratulates her personally. “We regret the deception,” he smiles, “but your squads should be proud. You’ve yielded some valuable data.”

Kitty understands: this is another code.