C harles Schulz never much liked Valentine’s Day, and neither did his fictional creation Charlie Brown. As Charlie Brown says, it is the day that reminds us that, “nothing echoes like the sound of an empty mailbox.”

When Mr. Schulz died on this day nine years ago, bringing an end to the 50-year run of his supremely popular comic strip, Peanuts, it was exactly one day before he would ever have to witness another red paper doily or another message candy heart.

This weekend, audiences at the Martha’s Vineyard Regional High School’s production of You’re a Good Man, Charlie Brown will have a chance to reflect on Valentine’s Day’s dark side: the crushing insecurities and disappointments that have ever been as much a part of the holiday as hearts and flowers.

And they will have a chance to laugh about it all.

The musical opens with the show’s title song, an ensemble piece in which Charlie Brown’s friends catalogue the long list of his failures as a person. Charlie (played by Jerome Pikor and Austin Gampfer — the show is double cast) cannot fly a kite, he cannot pitch a baseball. At one point in the song Lucy (Hannah Marlin and Emily Mercier) takes Charlie’s face in her hands and says, “Now this is what you call a failure face. It has failure written all over it.”

Eventually, the ever-adorable Linus (Alex Roan and Amalie Tinus) offers up the feeble, “I think Charlie Brown has nice hands.” By the end of the song, though, Charlie is held high in the air on the arms of the crowd, who find something, inexplicably, to celebrate in this supreme nonentity.

As Charlie’s insecurities play out over the course of the show (will he EVER get up the nerve to go talk to the cute red-headed girl?), the other members of the gang have problems of their own to work out. It turns out that in the seemingly safe and small world the children inhabit, bounded by the edge of the front yard and the schoolyard, untold psychic horrors lurk.

Early in the first act, the normally ebullient Sally (played by Emma Frizell and Rosie Bick) turns to Charlie and says, “I was jumping rope and suddenly it all seemed so futile.”

Soon the existential crises are falling thick and fast.

Linus, an inveterate thumb-sucker looks up from his thumb in horror and says, “I think I’m losing flavor.”

We then discover that even Snoopy’s (Katy Clark and Taylor Stone) doggy soul is rocked, from time to time, with yearnings that threaten to tear him apart.

One moment he is a well-loved dog, certain of his place in the world. “They like me, I think they’re swell, isn’t it remarkable how things turn out so well!” he sings. Then, when Charlie leaves he reveals to his bird friend Woodstock (Lisa Wilson) that he secretly longs to be a fierce jungle creature. Later we discover that he suffers from itchy teeth, a deep desire to bite something that comes upon him unbidden every day, and which he must beat back furiously for fear of being cast out of the warm web of his family’s affection.

It seems that all of the characters are dogged by the desire to be something they are not, or to have something they can’t get. Lucy wants to be a queen, Charlie wants to be an incredibly athletic and heroic fictional character called Flash, and Schroeder wants to be Beethoven.

As they cruelly cut one another down, they nonetheless help each other in the process of self-realization. When Schroeder tells Lucy that she is “a very crabby person,” and that she ought to try to obey Socrates’ injunction, “Know thyself,” she is at first indignant. What does Socrates have to do with it, she says. “Did she ever get to be queen?”

After conducting a thorough survey of her peers (to give some idea of how far she has caved at this point, her survey asks test subjects to rate her physical appearance as “(a) Stunning, (b) Mysterious, or (c) Intoxicating”), Lucy finally determines that she is, indeed, considered a crab.

Finally, even Lucy’s vast reserves of self-confidence give out. Luckily she has her little brother Linus’s affection to fall back on. This is the way it seems to go in the Peanuts world. After everything goes wrong and the ego is stripped totally bare, there is yet one grain of sweetness that allows the characters to keep on keeping on.

The show is relentlessly funny. In her tour de force, Philosophy, Sally cruises through several “philosophies,” trying each one on with great fervor and even greater brevity until Schroeder, the egghead eternally pained by the brutishness of the hoi polloi, excuses himself to go and practice Chopin.

Or there’s the song where Lucy decides to educate Linus, “See that eagle! When it is little it is called a sparrow!”

The energetic ensemble cast bursts with life and energy under the direction of Kate Murray, with especially good performances by Amelia Tinus and Alex Roan. Chad Curtis’s cartoonish pastel set design is an eye-pleaser, and the band, led by Michael Tinus, is in great form.

And fear not — You’re a Good Man Charlie Brown does at last offer the feel-good punch we so need on this dark holiday.

You’re a Good Man, Charlie Brown opened last night and plays again tonight at 7 p.m.; shows tomorrow are at 2 p.m. and 7 p.m. Tickets are $7 for students and seniors, $10 for adults.