★ ★

With Valentine’s Day, New Year’s Eve, and now Mother’s Day, director Garry Marshall is becoming a one-man cottage industry as he churns out sweet-toothed cinematic confections set on popular holidays, each of which serve up stellar (if mostly wasted) ensemble casts, blandly forgettable humor, and Hallmark-style romance spread over multiple story lines that occasionally cross-pollinate one another. It’s the Whitman’s Sampler approach to filmmaking: just throw in enough choices and chances are you’ll like something.

Mother’s Day juggles five all-too-familiar plot lines, and gets off to an awkward start with a voice-over by Penny Marshall describing the various trials a mom faces. As she explains these thankless tasks, we watch a harried mother attempt to get her stubborn daughter to the school bus on time. But neither Marshall nor the mom have anything to do with the stories we’re about to watch. Why are they there? Why not start with Jennifer Aniston, the film’s lead? Unfortunately, this is only the first of many wrongheaded choices on display. We are then quickly introduced to the quintet of story lines, each one populated with stock characters lifted from literally hundreds of other movies. There’s the pretty but insecure single mom (Aniston), whose handsome ex-hubby (Timothy Olyphant) married a sexy young plaything (Shay Mitchell). Of course, the single mom crosses paths with a recently widowed dad (Jason Sudeikis) who is clueless when it comes to raising his two daughters. We also get the lonely, high-powered career woman (Julia Roberts) who sacrificed love for ambition; bigoted, redneck parents (Margo Martindale, Robert Pine) dealing with adult children (Kate Hudson, Sarah Chalke) they deem to be rebellious; and the adopted young woman (Britt Robertson) with commitment issues longing to meet her biological mother.

Director Marshall and his four screenwriters desperately try to inject humor into each story thread, but end up producing more chuckles than laughs. Tired pratfalls, routine sight gags, and mildly racial jokes are continually offered up for amusement. It’s pretty telling when a scene in which standup comics perform at an Atlanta comedy club is the least funny bit in the entire movie. If you want laughs, stick around for the end credits when a series of bloopers unspool: These silly, unplanned gags provide the film’s funniest moments by far, with Julia Roberts’ off-color comment about a passing train a particular highlight.

The movie’s major drawing card is its top-tier cast, and each one outperforms the material he or she is given. Aniston is especially good, proving once again she is a formidable actress with great comic timing. Ditto for the Oscar-winning Roberts, who must feel a tremendous debt to Marshall for casting her in Pretty Woman, her breakout role back in 1990. How else to explain her acceptance of underwritten supporting parts in this picture and Valentine’s Day? The other standout is Hudson, who is a pure delight to watch and possesses a grounded, true-to-life personality that is undeniably appealing. But she is given precious little screen time in an overstuffed, unwieldy movie that badly needed further editing. At nearly two hours, this Mother overstays her welcome by at least 30 minutes.

With a trilogy of sorts now completed, one hopes the talented Marshall, who also helmed the terrific Runaway Bride and the pleasing Princess Diaries series, will lose his holiday spirit and return to single-story films.