Septuagenarian Dustin Hoffman makes his directorial debut with Quartet, a slight but immensely charming romantic comedy that is perfectly performed by a regal cast headlined by Maggie Smith, Tom Courtenay, Billy Connolly, and Pauline Collins. Oscar-winning screenwriter Ronald Harwood (The Pianist) adapted his 1999 play, which was inspired by Tosca's Kiss, a 1984 documentary about a home for retired opera singers in Milan. In Quartet, the setting is Beecham House, an opulent English estate that is home to Britain's finest retired opera singers and musicians. Beecham's residents are a spry, if aged, bunch. They may no longer be young, but their zest for life remains undiminished. This youthful exuberance is readily seen in flirty Wilfred Bond (a delightful Billy Connolly), whose randy but innocent talk generates much of the film's laughter, and in perpetually happy Cissy (Pauline Collins), a sweet soprano in the early stages of dementia. More serious is tenor Reginald Paget (Tom Courtenay). He teaches a music-theory class to local students who are more interested in rap than opera. But Reggie's sedate world, and indeed, the entirety of Beecham House, is upended when diva extraordinaire Jean Horton (Maggie Smith) reluctantly arrives. As one resident says, "She's as large as life and twice as terrifying." And Jean more than lives up to that billing, as Smith expertly spouts tart retorts to unwitting underlings that would make Downton Abbey's Lady Grantham proud. Reggie is unhappy to see Jean, not because of her reputation, but because he was once married to her for an all-too-brief time. To say things ended badly between them is an understatement: He's never forgiven her for breaking his heart, and worse, he's never fallen out of love with her. Now here she is again, and her presence sends him into a funk, as he is forced to recall their painful past. But as fate -- or script contrivance -- would have it, the financially flailing Beecham House is hosting a fund-raiser in an effort to prevent it from closing its doors. Wouldn't it be great if these four honored opera stars, who once sang together in a quartet and all now conveniently live at Beecham, reunited one last time to perform at the benefit? That would certainly sell a lot of tickets. There's just one problem: Jean doesn't want to do it. "I was someone once," she says. She would prefer to live on her past laurels, rather than risk tarnishing her revered reputation. But Wilfred, Cissy, and eventually Reggie insist that she join them. What follows is fairly predictable, but also wholly satisfying. Hoffman obviously loves his actors (no surprise there) and lets them shine at every opportunity. He also gives ample screen time to real-life opera sensation Gwyneth Jones, who plays Beecham's reigning diva before the arrival of Jean, and allows her an aria. Hoffman, who is a trained pianist and once dreamed of becoming a jazz musician, pushes Quartet's sumptuous music to the forefront, and it's as important to the film as Harwood's delicate, witty script. The only surprising thing about Quartet is that Hoffman spent 45 years in front of the camera before he decided to step behind it. His assured debut, thin on plot but rich in performance and atmosphere, is a loving tribute to seniors, much like himself, and their ability to contribute meaningfully to society. And it serves notice that this talented rookie director just may have a future behind the camera.