SPLIT PERSONALITY

Comedian Dale Stein usually shows up with a cast of characters, and that is likely to be the case tomorrow evening at Blues Alley when she plays Nina Navarre, a "late bloomer" who was discovered at age 19 as an extra in "Ben Hur."

Also expected are a South Philadelphian who keeps an appointment with her probation officer; and Shane, a nightclub singer with an artificial brain. Chef and restaurateur Fifi Mouloir, who has authored "Cooking With Food" and invented such culinary delights as "Raison D'e tre" and "Fresh Fruit Compost," will host.

Stein uses song, monologue and mostly mimed props in the transformations in her new show. She will be backed up by a trio led by pianist Roy Barber. Caron Tate will be guest vocalist.

Asked if there is some of her in each of her characters, Stein concedes, "Some that I'll admit to -- I see it as a way to work out my schizophrenia."

-- W. Royal Stokes COMING UP CAJUN

"If you see us on stage, you might think we're a country band. But as soon as you hear my fiddle, you know it's Cajun," says Hadley Castille, who is known in the dance halls of south Louisiana as "the swamp fiddler."

While growing up in Opelousas, Castille learned to play Cajun fiddle from an uncle. Though his band features two electric guitars and piano, Castille mostly sticks to the traditional two-steps and waltzes he learned as a youngster.

Like any musician, Castille has his heroes, including Cajun fiddle legend Rufus Thibodeaux and Cajun popularizer Doug Kershaw. In fact, on Castille's latest album, "Going Back to Louisiana," Kershaw joins Castille for some high-flying twin fiddle leads.

Castille, who performs with his Cajun Grass Band at the Women's Club of Bethesda tonight at 7, says, "Twenty-five years ago, I would have been scared to play 'Jole Blon' outside of Louisiana."

So why has Cajun music and culture become so popular? "We play happy music," he explains, and adds, "Of course, we have the best food in the world."

-- Joe Sasfy JAZZ ON THE WING

"We used to make a joke of it," says Red Wing Blackbird Ragtime Band cornetist Dick Roberts of the band's first rehearsals in the auditorium of a psychiatric facility. "People used to say, 'It's a good place for you to rehearse because you're crazy trying to put that music together.' "

That was six years ago; today, the band boasts an album on the Stomp Off label and a book of more than 600 tunes covering the period 1890 to 1920.

The Blackbirds will play for dancing and listening Saturday, 8 p.m. to midnight, at a Potomac River Jazz Club monthly special at the Ramada Hotel in Lanham. The program will include rags, cakewalks, tangos, hesitation waltzes and concert pieces. For information call 698-PRJC. -- W. Royal Stokes