To everyone's surprise, Marin's single, fifty-something mom, Erica Barry (DIANE KEATON), and Aunt Zoe (FRANCES McDORMAND) arrive on the scene. Everyone is fine with all four sharing the cabin, except for Erica, a successful playwright who doesn't approve of the May-December relationship, especially when she's all but given up on romance for herself.

Things take an unexpected turn when Harry has a sudden heart attack. The local doctor and big fan of Erica's work, Julian Mercer (KEANU REEVES), declares that Harry can't travel and thus must stay put until he improves. The only logical place for him to stay is Erica's place, another development she's not expecting, especially when everyone else returns to the city and then leaves them alone together.

Despite their differences, the two eventually start to become friendlier with one another, and with Harry and Marin mutually breaking up, romantic feelings begin to develop between them, much to their surprise. As longing turns into love, the two must figure out how to deal with their feelings and thoughts about what they should be doing in their lives, all while Erica must simultaneously deal with Julian falling for her.

Not only does a heart attack serve as a catalytic, life-changing event for a chronic lothario who never dates women over 30, but continued palpitations and other cardiac false alarms also serve their purpose in showing his now fragile state of mind about romance.

That might sound a bit heady, depressing and potentially tragic, but writer/director Nancy Meyers has nothing but a romantic comedy in mind with this offering. To her credit, the director of "What Women Want" and "The Parent Trap" has targeted her film not at the usual teen or twenty or even thirty-something crowd. Instead, she's aiming at those already in or nearing AARP age.

Of course, considering that Jack Nicholson ("About Schmidt," "Anger Management") and Diane Keaton ("Annie Hall," the "Father of the Bride" movies) are the potential lovers, that shouldn't really come as much of a surprise. Nevertheless, it's likely to be a welcomed and probably rewarded offering for a mostly underserved but large audience.

The result is a generally decently made and moderately entertaining if a bit overlong and otherwise unremarkable rom-com that showcases the talent of its stars. That said, the film is about as predictable as they come. Beyond the usual genre trappings, the plot arc follows a non-holiday, modified version of Dickens' "A Christmas Carol" (where a character gets a second chance at life). The stars also play out and off the same characteristics - Nicholson's devil may care rogue and Keaton's successful but somewhat self-conscious independent woman - that have fueled part of their careers.

Somewhat disappointingly, Meyers' early hints of a possibly more complex comedy never end up matching their potential. By setting up Nicholson's character falling for Keaton's just as an ER doctor - played with low-key charm by Keanu Reeves ("Hardball," the "Matrix" films) - the stage initially seems set for either a farce or a clever/satirical look at gender and age-based differences when it comes to romance.

There is a fair amount of the latter sort of material, but the film never goes as far as I hoped or imagined it might. The triangular relationship simply isn't as pointed or interesting as it needs to be. That's particularly true in terms of showcasing the differences in men of varied generations pursuing a middle-aged woman who previously figured that romance for her was a done deal.

There are some individual funny moments - the look on Nicholson's face when his character wakes up next to Keaton's in bed is nothing short of priceless - and plenty of clever bits of dialogue. Yet, there aren't enough of them to make this a classic comedy along the lines of "Tootsie" -- and its look at middle-aged "women" and romance - or any number of other films that click and are snappy from start to finish. While I don't necessarily mind a film that takes it time, this one occasionally feels indecisive and lacking.

Despite the thespian caliber on hand, there are also a few moments that don't ring true from story and/or character standpoints. They include a confrontation between the leads outside a restaurant (stemming from Erica's somewhat questionably quick falling in love) and one of Keaton's crying sprees (that's supposed to be poignantly funny but starts to feel annoying from its obvious fakery).

The biggest disappointment to yours truly is the disappearance of the sister character played by the terrific Frances McDormand ("Almost Famous," "Wonder Years"). Despite getting prominent placement in the first confrontation between the leads (when her character is introduced as an obvious nemesis to Nicholson's), she all but disappears for the rest of the film.

The same holds true, but to a lesser degree, for the supporting characters played by John Favreau ("Daredevil," "The Replacements") and Paul Michael Glaser (TV's "Starsky and Hutch") who appear to have prominent parts but are barely around. Meanwhile, Amanda Peet ("Identity," "The Whole Nine Yards") has a meatier part (the daughter of Erica and initial girlfriend to Harry) but then mostly steps back to let the stars do their thing.

All of that said, the film's various problems and deficiencies, whether considered independently or collectively, don't become a major hindrance to being able to sit back and enjoy the film for what it is. Although the parts don't terribly tax the leads' abilities, Nicholson and Keaton nevertheless are entertaining to watch and certainly seem to be having fun in their roles.

While it could have been so much better in terms of comedic and romantic story complications and developments, "Something's Gotta Give" is decent enough to earn a recommendation and a rating of 6 out of 10.