A year into the biggest project of their career, a lost letter made the developers of 1 World Trade Center start from scratch. Vanity Fair has a preview of the new documentary 16 Acres, which chronicles the challenges and conflicts that surrounded the redevelopment of the iconic structure. Months after the cornerstone for 1 World Trade Center had already been laid, security concerns from the New York Police Department halted construction and forced a redesign of the entire project at a cost of $20 million. Seven months earlier, the NYPD had written up their security assessment in a physical letter and mailed it to the New York Port Authority, the tower’s co-developer.