One key aspect of his job, says music supervisor Randall Poster, is to find the songs that can best shed light on the inner life of a character. And few characters have needed that kind of illumination more than Vincent, the enigmatic, curmudgeonly, alcoholic Vietnam vet played by Bill Murray in “St. Vincent.”

As the film unfolds, it reveals the secrets of Vincent’s life, but lyrics such as “Don’t you want somebody to love?”; “I fought the law, and the law won”; and “’Twas in another lifetime, one of toil and blood” offer insight into his soul.

“We wanted to use music to place Vincent in time, to be a foundation,” says Poster, “and to help establish a world for a character who is quiet about his own past.”

The challenge, of course, was to get clearances for such iconic tracks as Bob Dylan’s “Shelter From the Storm.” “We worked hard and used all our creative assets to get what we wanted,” Poster says. That included leveraging his “longstanding relationship with the Dylan camp,” dating back to Todd Haynes’ 2007 “I’m Not There,” which used about 40 of the tunesmith’s songs.