'It Ends With Us' screenwriter on landing a Taylor Swift song for the movie's soundtrack: 'It's as if she wrote it for this'

• Blake Lively's new movie, "It Ends With Us," features a Taylor Swift needle drop during a key scene.
• Screenwriter Christy Hall spoke to BI about her reaction to getting the cosign from Swift.
• Lively shouts out Swift in the closing credits for her undisclosed contribution to the film.

The emotional climax of Blake Lively's new movie, "It Ends With Us," features a Taylor Swift song so fitting that "it's as if she wrote it for the movie," according to screenwriter Christy Hall.