The old Broadway musical "A Funny Thing Happened on the Way to the Forum" can be a glorious show, but the funniest things seem to have gotten lost on the way to the Alden Theatre at McLean Community Center.

CAST in McLean has decided to have yet another go with "Forum," which the company performed during its 1993-94 season.

CAST (Community Alliance Supporting Theatre), which stages only the most frequently performed chestnuts of the American musical stage, has contrived a production that lacks any compelling or innovative sparkle to justify another revival of the 42-year-old comedy.

"Forum" is a zany laugh-fest, but it requires imaginative staging to overcome its dearth of nuance, witty dialogue or memorable songs. A rare full-fledged, professional production of the show from Arlington's Signature Theatre at the beginning of the now-concluding season offered a definitive, inventive staging that should have scared off other area troupes from attempting the show for some time.

Unfortunately, CAST in McLean didn't heed the warning.

With a 1962 script by Larry Gelbart (television's "M*A*S*H") and Burt Shevelove, "Forum" is all-out silliness, consisting mainly of spectacle, gags and shtick. Its music and lyrics by Stephen Sondheim include simple songs designed only to support the comedy, most of which are forgettable, except for the mesmerizing and rousing opening-and-closing number "Comedy Tonight" and the sly, melodic "Everybody Ought to Have a Maid."

The story involves Pseudolus (Mike Baker Jr.), a slave in ancient Rome who will win his freedom if he can fix up his young master, Hero (Michael A. Dzbenski), with the virginal Philia (Martha Britton Eller). She lives next door in a house of ill repute and has been sold to vainglorious warrior Miles Gloriosus (Jay Tilley).

From there, the plot descends into convoluted high jinks.

Some of the musical numbers in the CAST production sound wonderful, but much of the acting is flat, with important roles filled by players seemingly chosen for their vocal skills rather than thespian ability.

Director Roland Branford Gomez has substantially toned down the bawdiness the show requires, adding to its blandness.

Talented local theater stalwart Baker is competent as the clown-like Pseudolus, but he is too polished to descend into true silliness and thus provides few sparks. Secondary leads Dzbenski and Eller both sing magnificently, but neither displays substantial acting ability, and numerous comic opportunities are squandered, particularly in the usually hilarious send-up number "Lovely," which they inexplicably perform straight.

It is left to cast members in secondary parts to steal the show, particularly Tilley, whose robust voice soars in "Bring Me My Bride" as he wallows ridiculously in the character's vanity. Tilley also dominates the melodramatic anthem "Funeral Sequence" with a charismatic and powerful performance. Making his stage debut, Dennis Neason, the only other actor to consistently go over the top, is hysterically funny, appropriately enough, as frantic slave Hysterium. Ed Broyles, as Hero's lecherous father Senex, also provides some amusing characterizations.

The production seemed under-rehearsed opening night, with the orchestra, directed by the ordinarily superb Jeffrey F. Shue, sounding ragged in places and the choreography from Tammy Roberts tentatively executed. Roberts, a supremely talented singer and actress, performed in Signature's production of "Forum" but was unable to transfer the magic.

Jon Downing's sets and Richard "Bat" Battistelli's costumes are imaginative and colorful, but not enough to compensate for the lack of vivacity. It's possible things may improve as performances continue and the cast warms to its task, but on opening night, "A Funny Thing" just wasn't happening.

"A Funny Thing Happened on the Way to the Forum," performed by CAST in McLean, concludes its run this weekend. Showtime is 8 p.m. tomorrow and Saturday at the Alden Theatre, 1234 Ingleside Ave., McLean. For tickets, call 202-432-7328 or visit www.ticketmaster.com/venue/172035. For information, visit www.castinmclean.org.

Jay Tilley, as Miles Gloriosus, steals the show in CAST in McLean's production of "A Funny Thing Happened on the Way to the Forum."