THE DIARY OF A TEENAGE GIRL Trailer Debut Watch the first THE DIARY OF A TEENAGE GIRL trailer! The film, directed by first timer Marielle Heller, stars Bel Powley, Alexander Skarsgård, Kristen Wiig, and Christopher Meloni. THE DIARY OF A TEENAGE GIRL will be released in theaters on August 7. A teen artist living in 1970s San Francisco enters into an affair with her mother’s boyfriend.