STAGE REVIEW : Breathtakingly Brain-Twisting : Theater: ‘Solitary Confinement’ has enough surprises to impress even the most jaded of mystery-genre fans.

“Solitary Confinement,” Rupert Holmes’ newest thriller, is a duel of wits.

On one level, the conflict is obvious in the show, which opened Sunday at the Spreckels Theatre: Richard Jannings, an eccentric billionaire businessman played by Stacy Keach, thinks he is secure in his electronically fortified castle in Albuquerque, N.M. Until someone threatens to kill him.

The thrill of the show comes from how that person tries to get to Jannings and how Jannings retaliates. The resulting duel is between the two as well as between Holmes and the audience.

Because the show’s surprises and twists are what makes the show, none of the tricks can be revealed here.

But one promise can be made: Lurking in this sumptuous, craftily appointed set are surprises guaranteed to steal the breath of even the most jaded mystery-genre fans.

Keach is what makes the show work. He starred in its premier at the Pasadena Playhouse, where it played to sold-out houses throughout December, and he will continue to star in it at the Kennedy Center in Washington and, opening April 22, at the Ambassador Theatre on Broadway.

It is a pleasure to see Keach at the top of his craft--he is fully in control here, relishing every moment.

The show has a tendency to become too talky, with too little of the talk going anywhere. Still, “Solitary Confinement” calls on quite a few resources from the actor’s bag of tricks. And, thanks to Keach and an expert artistic design team, the effects are indeed dazzling.

What can be told is that Jannings puts in a 9-to-5 day (although for him, that means 9 p.m. to 5 a.m.) in his state-of-the-art mansion. He prefers to interact with his electronic toys rather than with people. In fact, he limits his communication with his staff to a one-way video monitor.

At whim, he flips a switch and badgers the cook for yet another elaborate, highly specific gourmet meal that sends the poor fellow scurrying out to the midnight market. He presses his spinsterish research assistant to find out definitively what came first, the chicken or the egg. He callously fires a security guard for being too old, and he baits his mousy senior vice president just because he feels like being a creep.

Aman’s home is his castle, as the saying goes. For Jannings, as he smugly puts it, his castle is his castle. And he rules it like a king.

Until there’s an attempted coup d’etat that sends him back spinning to his own resources, unsure of whom he should count among his enemies or his friends.

This is not Shakespeare, which Keach has also done to acclaim. Those looking for depth had better look elsewhere. Character development is not what this show is about, either, although some broad, unconvincing strokes are made toward Jannings’ ultimate change into a nicer guy.

Writer Holmes is an inventive master of suspense. He won two Tonys for “The Mystery of Edwin Drood,” a musical whose title was shortened to “Drood,” in which the audience got to pick the killer. He also penned the non-musical thriller “Accomplice,” which sold out at its Pasadena Playhouse premiere but went on to flop on Broadway.

Holmes has assembled a top-notch team to put “Solitary Confinement” together. Although the show could use some tightening and sharpening, the direction by Kenneth Frankel delivers plenty of knockout punches. The clever scenery design and art direction by William Barclay set up key moments beautifully, and the costumes by Kathleen Detoro seem at once effortless and inspired.

Aiming a show toward Broadway is itself a suspense-filled enterprise. But, for this crowd-pleaser, the biggest surprise would be if it didn’t make it in New York.

“SOLITARY CONFINEMENT”

Written by Rupert Holmes. Director is Kenneth Frankel. Set design and art direction by William Barclay. Lighting by Donald Holder. Costumes by Kathleen Detoro. Sound by Jack Allaway. Production stage manager is Joe Cappelli. Stage manager is Arthur Gaffin. Music production by Deborah Grunfeld. With Stacy Keach, Samuel Tate, Art Calvin, Yves Konstantine, Edward Allesandro, Carl Huffman and Jane Rollins. At 8 p.m. Tuesday-Saturday and 7 p.m. Sunday, with Saturday and Sunday matinees at 2. Through Jan. 26. Tickets are $10-$35. At the Spreckels Theatre, 121 Broadway. Call 235-9500 or 278-TIXS.