They called him Dean Calendar because one morning in 1984, he didn’t just call in sick—he erased Monday. Dean worked payroll at a paper company in Dayton, Ohio. He was quiet, wore a clip-on tie, and knew the mainframe better than his manager. Every Monday, he watched the same scene: groans, coffee, and complaints about the week starting again. One night, he found a hidden test file meant for daylight savings time. Instead of adjusting the clock, he changed something else. He renamed Monday to “Part 2 of Sunday,” and the system believed him. Payroll skipped the date. Checks still cleared. Nobody noticed. Dean started applying the same trick to other branches, quietly, after hours. By winter, five offices had no Mondays. Trucks arrived off-schedule. Flights were missed. Morale went up anyway. When IT tried to fix the bug, things got worse. For twelve hours, the system jumped from Sunday straight to Tuesday. Monday didn’t exist on any of their charts. Only one name showed up in the error logs: Calendar.D. When they went to Dean’s apartment, it was empty. No forwarding address. Just a sticky note left on the desk. “If you can read this,” it said, “it’s Tuesday.”
