And with the epically tall, jock-handsome Del Negro in a part Joe Mantegna originated, the character radiates such golden-boy confidence that one can't believe he'd have much use for a merely cute flunky like Campbell's Karen.

Greco lets the lines breathe — her cast's naturalistically varied delivery avoids that Morse-code monotony the playwright prefers for his staccato Mametspeak. But she doesn't lend much weight to the ultimate question of who's manipuutf8g whom, as this production's Karen doesn't seem capable of calculation. The lack of ambiguity makes this a frequently very funny Speed-the-Plow, but sans much suspense or climactic sting. *

SPEED-THE-PLOW

Through Feb. 3

Tues.–Sat, 8 p.m. (also Wed. and Sat., 2 p.m.; no matinee Wed/16); Sun., 2 p.m.; $14–$82

American Conservatory Theater

415 Geary, SF

(415) 749-2228

www.act-sf.org