Watch Meryl Streep in 2015's Jonathan Demme-helmed "Ricki and the Flash," where she starred as a free-spirited, leather-clad musician fronting her own rock-'n'-roll cover band, and then watch her in "Florence Foster Jenkins," where she portrays a real-life socialite and heiress in 1940s New York whose passion for music and performance supersedes her inability to carry a tune. Aside from their shared interest in singing, there are few, if any, similarities between these two diametrically opposite figures. It is, of course, no secret Streep is a second-to-none chameleon within her acting field, but to see these two pictures a year apart is to be reminded once again how fully and seamlessly she can disappear into any role she takes on. Delivering consistently nuanced, typically astonishing performances ultimately means she is frequently better than the films she is in, and so it goes with "Florence Foster Jenkins." Directed by Stephen Frears (2006's "The Queen") and written by Nicholas Martin, this genial biopic, centralized to the final year of Jenkins' life, is wispy and low-key, a little funny but not uproariously so and a little touching but mostly in its home stretch. Even as the film threatens to drift away like the seed head of a dandelion flower, Streep and co-star Hugh Grant (2015's "The Rewrite"), as Jenkins' longtime partner St. Clair Bayfield, ground the proceedings with the lived-in affection and familiarity of a couple who share a long and storied past.

Florence Foster Jenkins (Meryl Streep) is, perhaps, best known in exaggerated terms as one of the worst singers who ever lived. A tone-deaf operatic soprano who had particular trouble hitting the high notes, she dedicated her life to the arts and, one month prior to her death, performed to a sold-out crowd at Carnegie Hall. As this film tells it, she was entirely oblivious of her deficiencies until she received scathing newspaper reviews following her concert. The claim that she was "the worst singer in the world" is hyperbolic in the extreme. Indeed, her voice was radically uneven and could be grating every time she hit a bum key, but there were other instances when it almost sounded proficient, her exuberance for performing transcending her lack of technical merit.

On a writing level, "Florence Foster Jenkins" rarely penetrates the surface of who its title figure is, but Meryl Streep brings an added layer or two to a somewhat slight role. Little is learned about her past other than that she owns her own nightclub, The Verdi Club, and has lived for years with the unpredictable, at times debilitating, effects of syphilis. Her naiveté over her singing voice is unexplored but seems to spark from no one being truthful with her. What can be deemed is how infectious Streep makes Jenkins, refusing to allow anything to stand in the way of the dreams she has set for herself. Her relationship with St. Clair Bayfield, a Shakespearean actor who loves Florence but cannot be intimate with her, is complicated yet pure. Though St. Clair lives something of a double life, balancing his time between Florence and younger girlfriend Kathleen (Rebecca Ferguson, in a thankless turn), the viewer understands the complexities of his predicament, and Hugh Grant avoids the dangers of turning him into an unfeeling cheater or a dog. His adoration for Jenkins is never in question. In a delicious supporting part, Simon Helberg (TV's "The Big Bang Theory") is a standout as the quirky, forever smiling Cosmé McMoon (Simon Helberg), a pianist Florence hires and befriends.

There is nothing especially revelatory about "Florence Foster Jenkins" as a whole, but it is worth noting director Stephen Frears never turns his protagonist into a punchline or subject of ridicule. Instead, she—and her story—is told with a warm, empathetic touch, one of Florence's final lines so simple yet so moving it has the power to catch in one's throat. Florence Foster Jenkins sang not because she was great at it, but because it was what she felt, deep down inside, she was meant to do. It's no surprise others followed.