If you were categorizing William Shakespeare’s Twelfth Night, it would certainly be one of the Bard’s comedies, even though the current Palm Beach Shakespeare Festival production emphasizes the play’s melancholy side. And not just because the action begins with a shipwreck.

At Jupiter’s Seabreeze Amphitheatre in Carlin Park, where the show continues through Sunday evening, that ship has been turned into a South Pacific Airways plane. It crashes with high impact, thanks to the efforts of production designer Daniel Gordon and the sound effects of Chris Bell, dumping the passengers — including grown twins Viola and Sebastian — onto the tropical island of Illyria.

Fortunately, the play then proceeds with relative fidelity to Shakespeare, even if the final moments throw everything we have just seen in doubt. Naturally, that has a way of putting a damper on the original happy ending.

Otherwise, this Twelfth Night is typical Palm Beach Shakespeare Festival. It features a few fine performers in key roles and almost as many in support that are simply not up to the task. Still, in its 22nd year of presenting outdoor theater, the festival continues to offer an evening’s sort-of-classical entertainment free of charge, drawing sizeable throngs of modern-day groundlings.

The play is a buffet of familiar Shakespearean plot devices, including mistaken identity, gender confusion, cruel tricks played on the pompous and, eventually, the enduring power of romance.

Separated from her brother in the crash, Viola (an assured, verbally adept Krys Parker) dons a vanilla-colored three-piece suit and passes herself off as dude Cesario in order to better find her twin, Sebastian. She — as a he — quickly attracts the romantic attentions of countess Olivia (a too bland, girlish Katherine Seldin). Cesario/Viola counters by encouraging Duke Orsino (in-over-his-head Jim Brogan, curiously miscast as a black-clad, long-haired Steven Tyler-like rocker) to woo Olivia, but he too becomes smitten with Cesario.

Appearing in his third Twelfth Night with the company, Kevin Crawford both directs this production and excels as Olivia’s puritanical steward Malvolio, easily duped into believing his mistress has romantic feelings for him. As always, Crawford handles the Elizabethan dialogue with conversational ease, and earns the show’s biggest laughs reading a forged love letter. Costume designer Penny Williams also has fun dressing Malvolio in solar system-patterned pajamas and, later, an unsuitable suitor’s outfit of kilts and cross-gartered yellow stockings.

Other assets are Missy McArdle as quick-witted fool Feste, who sings most of her riddled wisdom, Alan Gerstel as inebriated Sir Toby Belch, who lives up to his name, and Laura Ruchala as Olivia’s saucy servant Maria.

As Palm Beach Shakespeare audiences have probably come to expect, this Twelfth Night is undeniably uneven, but worth the admission price. Donations are accepted, allowing theatergoers to pay — as the play’s subtitle puts it — What You Will.