After six years as a Broadway fixture, Dear Evan Hansen is waving goodbye through a window. The show that gave rise to Ben Platt, the Pasek-and-Paul musical-industrial complex, and an endlessly memed film adaptation will sign off on September 18 after 1,678 performances. By then, Evan Hansen will have secured its place in history as the 47th-longest-running show on Broadway — if it didn’t already have one for innovation in film depictions of high-schoolers. When the show premiered in 2016, it was lauded for its discussion of mental illness and its sense of humor and became a rare original hit. It launched the careers of composers Benj Pasek and Justin Paul, who went on to write the music for La La Land and The Greatest Showman; Evan Hansen became a plum role on Broadway, with Noah Galvin and Jimmy winner Andrew Barth Feldman notably stepping in; it won six Tony Awards. But more than all that, it made the original star, Platt, inescapable for a moment, culminating in his reprisal, at nearly 27 years old, of the role of a 17-year-old. Less than a year later, the Broadway has no havoc left to wreak. Sincerely, Dear.