The West End Dinner Theatre's midsummer menu is offering a good, old-fashioned, musical-comedy murder mystery.

Okay, it might not be old-fashioned, but this chow-biz production of "Something's Afoot" is undeniably good.

A deliberately ridiculous creation of James McDonald, David Vos and Robert Gerlach, this dark-humored, mid-1970s farce is a spoof of the conventional whodunit, particularly those old Agatha Christie standards.

In fact, the plot sounds like any number of Christie mysteries. A slew of unlikely bedfellows are invited to spend the weekend at a manor house. A storm cuts them off from the mainland. The owner of the estate (Dudley Rancour) has been killed. A will is missing. An unexpected guest arrives, and the guests are murdered one by one.

But at any moment--appropriate or inopportune--the cast erupts into song. The tunes aren't memorable, but the lyrics are clever and contain many of the show's funniest lines.

And unlike the intellects who fill the bill in traditional mysteries, the whole assemblage at Rancour's Retreat is more than a few bricks short of a load.

Director Larry Baird, staging a show at Alexandria's West End for the first time, has orchestrated a perfectly timed comic spectacle, loaded with clever sight gags and witty dance steps. Baird is also a choreographer along with Mark Minnick, who does a wacky turn as Clive, the butler.

A 10-member cast rips through this fast-paced production in one of those tight ensemble performances that appears to be as much fun for the actors as it is for the audience.

Leading the pack of hapless guests is Miss Tweed, the obligatory elderly amateur detective, who investigates crimes with an air of authority, fueled by sherry. Monica Lijewski plays the snoopy spinster with zeal.

The stock high-society grande-dame, Lady Grace Manley-Prowe, is portrayed charismatically by Anita O'Leary, who opened the show Saturday as the emcee with the ad-lib facility of a stand-up comedian.

Lady Grace's paramour, Col. Gillweather, played by Frank Marino, gets his laughs in the last five minutes of his life after being stuck with a poison dart and counting down the time with stereotypically British calm in the face of disaster.

Other highlights include an over-the-top performance of "The Legal Heir" by Thomas Howley as Nigel Rancour, the greedy nephew; "I Have a Teeny Little Dinghy," by James E. Lawson, a lecherous caretaker who plans his escape with the buxom maid, played for good laughs by Tricia Scott; and a deadpan portrayal of Hope Langdon, the blithely stupid ingenue, by Mary P. Payne.

A live, six-piece band, directed by Brendan J. Sheehan, sounds more substantial than you would expect from a small ensemble.

The only troublesome technical flaw in the production is an amplified recording that is supposed to reveal the entire motive for the murders, but instead sounds almost as garbled as the station announcements aboard the Metro.

G. Spencer Barrett II, who does a short-but-bright appearance as Dr. Grayburn, has designed an elaborate set filled with absurd booby traps. Props are provided by Joey Wallen, who appears in a likable performance as Geoffrey, the unexpected guest.

Barrett's set and a colorful array of costumes designed by Charlotte Souders add considerably to the zany flavor of West End's appetizing midsummer spoof.

"Something's Afoot" continues Tuesdays to Sundays through Aug. 29 at the West End Dinner Theatre, 4615 Duke St., Alexandria. Tickets range from $30 to $35, depending on the day and time of show; $20, children ages 12 and younger. Call 703-370-2500 for reservations, or check the theater's Web site, www.wedt.com, for more information.