The cousins, who both live in Willow Glen, are nephews of Michael Mulcahy, CMT's former artistic director. Both Michael and his sister Paula performed extensively with the company in their youth.

"I used to watch my uncle Michael do a lot of [alumni reunion] shows here," Frankie says. "Reading his and Paula's résumés was really inspiring."

Frankie, 18, a senior at Lincoln High School, is playing sadistic dentist Orin Scrivello in CMT's production of Little Shop of Horrors. Tucker, 17, portrays Mr. Mushnik, owner of the flower shop where Audrey 2, a man-eating plant from outer space, puts down roots.

Both roles present challenges for the young performers. Tucker is playing a man old enough to be his grandfather, while Frankie is stepping into the shoes filled by Steve Martin in the film version of the production.

Before the play opened, Frankie admitted, he was feeling nervous. "Everyone's seen the movie," he says. "Everyone's going to expect that on stage."

Tucker, on the other hand, has played gentlemen of a certain age before, most recently in The Will Rogers Follies. To create these characters, he says, "I basically take stuff from ornery old people I know."

Little Shop marks Tucker's 24th show with CMT and Frankie's sixth.

"I'd been trying to convince Frankie to do shows here for years," Tucker says. "Despite what he says, he has a really good voice."

"I was too busy playing sports," Frankie explains.

Both Mulcahys say they've made good friends with fellow CMT cast members.

"You've found a few girlfriends here," Frankie teases Tucker.

"Most of my best friends are from CMT," Tucker says. "It's different from just meeting people at school, because you're all here to do the same thing, and you all have a common interest.

"Another good thing about working here is that you get good stage effects that you could never get at a high school," Tucker says, citing the revolving stage in West Side Story and the elevator in Tommy that delivered the title character to the stage.

Audrey 2 is another case in point. Assembled from three pieces, the carnivorous plant is 10 feet tall and features petals that open and close when it speaks, sings or feeds.

"We didn't expect a cardboard plant," Tucker says. "We've come to expect something really good."

In spite of their family ties to former CMT staff, the cousins agree that current artistic director Kevin Hauge is great to work with.

"He has a vision, and he's really good at getting performers to do what he wants," Tucker says. "He's got a good attitude: He's always cracking jokes, but he keeps it professional."

While Tucker says he'll probably study acting in college, Frankie says he's more interested in performing as a hobby. Depending on where they attend college, the two plan to keep performing with CMT until they age out at 20.

"I've been doing it for so long that it's like family here," Tucker says. "It's a lot more fun than school."

"Little Shop of Horrors" runs March 5­14 at the Montgomery Theater, Market and San Carlos streets, San Jose. Tickets are $12 to $18. For more information, call 408.288.5437 or visit www.cmtsj.org.