EVEN THE NOVICE sleuth should find it easy to stay one step ahead of the murderous machinations in "Corpse!," a new mystery spoof in the tradition of "Sleuth" and "Deathtrap."

Like its predecessors, the payoff is more in chuckles than chills for this British import, which is having its pre-Broadway tryout at Baltimore's Morris A. Mechanic Theater.

It's a tale of murderous intent between identical twins, set in 1932 England. But "Corpse!" is not so much a "whodunnit" as a "who was it dun to?" Though bodies appear and disappear with amusing, confusing profusion, playwright Gerald Moon's situation is disappointingly predictable, a flaw he covers up with some perverse comic touches and a few shakes of Shakespeare.

Original "Sleuth" star Keith Baxter again assays multiple personalities as Evelyn and Rupert Farrant, identical -- but very different -- twins. Evelyn, a down-at-the-heels cracked actor, wants to extinguish his distinguished sibling Rupert, a well-to-do bachelor about to sail off with the soon-to-abdicate King of England.

Chameleonic Baxter -- when we see him in the first of many faces, he is in lowest drag, like a superannuated refugee from "La Cage" -- flashes deftly back and forth between personas. Though he chews more than a few of his lines and bellows some others, Baxter's presence invigorates the play.

Milo O'Shea's famous eyebrows are more imposing than ever, and he waggles them ferociously in his dependably endearing turn as Major Ambrose Powell, the befuddled ne'er-do-well hired by Evelyn to do in his brother. O'Shea skillfully handles a novel bit of slapstick that calls for re-animating a corpse when the tipsy landlady stumbles in to visit.

Alan Tagg's clever turntable set neatly makes the switch from Evelyn's grubby basement flat to Rupert's Deco digs, though the walls shake unnervingly at key moments, and some of the appointments are too tatty- looking for Rupert's posh place.

Tagg's ingenious scheme of trapdoors and hidden exits, and director John Tillinger's deployment of body doubles, succeed in pulling the wool over our eyes even when "Corpse!" itself fails to fool us.

CORPSE! -- At Baltimore's Morris A. Mechanic Theater, through December 8.