In St. Vincent, 12-year-old Oliver (Jaeden Lieberher) and his recently-divorced mother (Melissa McCarthy) move to Sheepshead Bay, Brooklyn. Their introduction to their next-door neighbor is not a cheerful one. Vincent MacKenna (Bill Murray) is a grouchy old man who does not take kindly to the family's movers hitting a branch off his tree onto his old car and property.

When gym classmates at Oliver's private school take his school uniform with his phone and keys inside, Oliver comes home to an empty, locked and impenetrable house. As usual, his mother is at the hospital, working her long hours as a CAT Scan Technician. Vincent reluctantly lets the boy wait inside his dumpy house, treating him to some Abbott & Costello and a can of sardines and saltine crackers for dinner. That experience establishes Vincent as an unlikely go-to babysitter for Oliver. For $11 or $12 an hour, Vincent picks up the kid at school and lets him tag along on his daily routines, from the race track to his favorite bar.

One can easily question the wisdom of exposing a boy to the curmudgeon's many vices, which include smoking, heavy drinking, impatience, and swearing. The arrangement does arise as an issue in Mom's custody battle with her philandering ex-husband. But real world concerns are not high among St. Vincent's priorities. This is a film that wants you to get swept up in its world and to embrace this unlikely pairing of a cranky old man and a loner boy as beneficial to both parties.

Vincent teaches Oliver how to throw a punch when bullies at school warrant it. He also teaches him about the high-risk, high-reward nature of the trifecta bet.

St. Vincent may remind you of movies like Bad Santa and Bad Teacher, where an oft-inappropriate adult of questionable influence finds themselves in a position of authority among children. What you could retitle Bad Babysitter ends up being better than those comedies. Yes, it is contrived, formulaic, and somewhat predictable. Furthermore, much of the film simply does not work as intended, from Oliver's dealings with bullies to Naomi Watts as Vincent's regular prostitute, a thickly-accented pregnant Russian stripper (or rather scantily-clad dancer, this being a PG-13 movie).

What does work is Bill Murray. Every moment he's onscreen, there is something to like about this film. Murray sinks his teeth into a lead role that any actor of his age would relish. The character is a little shaky at first. Murray adopts a kind of iffy working class Brooklyn accent and his outbursts at societal standards (from bank lenders who cut him off with a shrug and a smile to telemarketers) feel a little stale and unoriginal. Eventually, though, Vincent wins you over, with Murray adding to his repertoire of surrogate father figures that includes Meatballs and Rushmore.

There are many layers to the character. One of them -- a subplot about money owned to a bookie (Terrence Howard) that literally goes nowhere -- is unnecessary. But several of them enhance our understanding of a grumpy pauper who's barely getting by on booze, cigarettes, a (photogenic) white Persian cat, and his paid sessions with Daka. The characterization reminds one of a pair of performances Murray turned in a decade ago in The Life Aquatic with Steve Zissou and Broken Flowers. While the film as a whole may be comparable to those two, Murray's work here feels a little sharper and more powerful. He's ten years older and it shows on his very aged face. Doing the opposite of what most actresses do, Murray is actually playing a character four years older than him. He got the part after Jack Nicholson, 77, backed out.

Once a brilliant mainstream comedian and major box office draw, Murray has been embracing indie roles with drama and pathos for over fifteen years now. He has been celebrated for it, most significantly for his Golden Globe-winning, Oscar-nominated turn in Lost in Translation. Murray could have gone the Steve Martin route and continued to make the same kind of vehicles to diminishing returns. Instead, he's challenged himself and been choosy. His work for a couple of trusted directors (Wes Anderson, Jim Jarmusch) has won him admiration and respect even if it continues to drag down his box office averages from his lucrative days as a multiplex attraction.

For awards purposes, St. Vincent will be classified as a comedy, which should virtually guarantee that Murray picks up a fifth Golden Globe nomination. But despite Murray's reputation as a comic virtuoso and the frequent laughs that marked my packed-full screening, the film is far more striking for its drama. It is remarkably touching at times, including for much of its final act. Some jokes land and some do not. But the dramatic material cuts you to the core with precision and may offer relief for those with habitually dry eyes.

St. Vincent would not be nearly as endearing with a different actor in the title role. Murray's forty years in entertainment have earned him goodwill that enables you to love his characters even when they're doing horrible things (and given his reasons, nothing Vincent does is all that horrible). Murray gets some fine support from newcomer Lieberher, who is precocious but likable; McCarthy, who shows off some fine dramatic chops and is spared even a single fat joke; and Chris O'Dowd, who delights as a warm, approachable priest/teacher at Oliver's school. Watts' comic material falls flat, but I don't think any actress (especially a recognizable one) could make it work. Howard's plot could be lost without any detriment.

Theodore Melfi has attracted an admirable amount of talent to this, his feature writing and directing debut. His screenplay is somewhat derivative, a bit green and often not as clever as it thinks it is, but he does a solid job as director and helps the movie reach a satisfying end through some pretty tricky and potentially treacly turns. Melfi also has figured out a way to make moviegoers sit through the end credits: have them appear over Bill Murray singing along with a Bob Dylan song while using a hose on his predominantly dirt backyard. Very few of those in attendance at my screening began filing out while those ran.

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