FOR SOME REASON, 1984 has been the year to play it fast and loose with the works of William Shakespeare. First we had Folger's splashy "King Lear," followed closely by Arena's spirited "The Tempest," both of which seemed to put special effects before all. Now, to usher out the year, Source Theater has turned in "Twelfth Night" as an irreverent pop romp.

When it was first produced (around 1600, for London's Christmas festivities), Shakespeare added the subtitle "What You Will" to his holiday farce. Source has taken that subtitle at face value, filtering the comedy by turns and with varying degrees of success through the styles of SCTV, Monty Python and the Three Stooges, with a few songs from the fool/narrator Feste a la "Pippin."

Not that "Twelfth Night" demands absolutely reverential treatment. It is one of the Bard's more high-spirited comedies, featuring one of the most unlikely love triangles in literature. Set in the delirious kingdom of Illyria, "Twelfth Night" contains a surfeit of (s)wordplay, long-lost twins, cross-dressing, multiple cases of mistaken identities and love at first sight, and a deliciously prankish revenge.

Director Joseph Banno has set a breakneck, athletic pace, allowing barely a pause for breath as Nike-shod actors run and jump on Joe Musumeci's set of wood-planked cubes. Though the rhythm is sometimes choppy, the speed suits the lunacy of Shakespeare's scenario. Banno has made sure his cast knows what the words mean, and the actors have a field day, with some fine comic turns and natural, if contemporary, mannerisms.

There are several noteworthy performances among the large cast. Katrina van Duyn gives us a self-absorbed Olivia, absent-mindedly aerobicizing while leafing through Self magazine, then changing into a sexual bundle of nerves after being smitten by Barbara Klein's spunky Cesario/Viola. Michael Willis is very funny as Olivia's tippling uncle Sir Toby Belch, crossing Jackie Gleason with John Candy, with a letter- perfect poke at television evangelist Ernest Angley. Jeff Peters plays Count Orsino as a khaki-clad, knotted-sweater yuppie, tossing off lines with a lecherous waggle of the eyebrows. Brian Nelson's Malvolio is comically malevolent, foppish and fey. And as Feste the fool, Derek Jones gets it just right -- his antic tone shows the smarts behind the silliness.

TWELFTH NIGHT -- At Source Theater's Warehouse Rep through February 2.