In July of 1984, an armed man walked into a McDonald’s in San Ysidro and murdered 21 people. At the time, it was the deadliest mass shooting in US history. The massacre created a strange dilemma for McDonald’s: what happened wasn’t their fault, but the event was becoming synonymous with their brand. The corporation decided to replace the branch’s windows, clean up the blood, and reopen their doors to the public. But the survivors had a different plan.