William Shakespeare's Macbeth is a wild untamed monster of a play. A good director knows when to feed the beast sedatives and when to set it free to roar its terrible roar and tear up all the sets. There are moments in director Lesley Schisgall Currier's uneven new staging of Macbeth, at Marin Shakespeare Company in San Rafael, when the monster does bare its teeth and even gets to growl a little. But it's not until late in the play that Macbeth's full ferocity is let loose, and then only briefly and due largely to the work of a few solid actors.

As is typical of Marin Shakespeare's recent efforts, the energies of the director seem to have been entirely focused on the visual "concept"—in this case, that Macbeth hallucinates a lot and is driven into a murderous frenzy by visions of ghostly mummified child-spirits making weird faces at all the wrong moments—while leaving the actors to grasp their own way through the play. Some, like William Elsman as Macbeth and Scott Coopwood as Macduff, do have memorable moments, though Elsman appears to have been given no clear map to guide him through Macbeth's complex series of sudden personality changes.

Many of the others, including the often superb Alexandra Matthew, are left to flounder in the flood of Shakespeare's wild shifts in tone. As Lady Macbeth, written as heartlessly bloodthirsty one minute and cowardly frail the next, Matthew (who certainly has the chops for this kind of role) looks, for all the world, like she's still waiting for notes from her director.

Though there are some truly effective moments in the production, including a brutal double-homicide that is nothing short of breathtaking, the horrific power of the play is constantly undermined by unfathomable bits of silliness, from the goofy, eardrum-blasting sound effects to the baffling insertion of the most overused word in bad-art history: "Noooooooooooooooo!"

MSC's other season-opening effort, The Complete History of America (Abridged), by Adam Long, Reed Martin and Austin Tichenor, is also a disappointment. My personal favorite of the many "reduced" shows now in the canon, History sinks or swims on its pacing and sense of comic drive. Under director Robert Currier, the disconnected series of comic-historical vignettes plods along without any real sense of momentum, frequently grinding to a halt for the actors to offer their own (not very funny) ad-libs. It's too bad, because in the right hands, this is one of the funniest shows about American history ever written.

'Macbeth' runs weekends through Aug. 14, and 'The Complete History of America (Abridged)' runs weekends through Sept. 25 at Forest Meadows Amphitheatre. 1475 Grand Ave., San Rafael. Showtimes vary. $20-$35. 415.499.4488.

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