Richard Montoya, long known to Southern Californians for his participation as writer/ensemble member in the sociopolitical comedy troupe Culture Clash, now debuts as playwright apart with  “Water & Power,” which premiered at the Mark Taper Forum in 2006. Thanks to San Diego Repertory Theatre, local audiences have an opportunity to see the extended one-act drama — filled with pain, pathos and humor — at San Diego Repertory Theatre through Nov. 16. Sam Woodhouse directs a fine company that includes founding Culture Clash member Herbert Siguenza, seen at the Rep in “Culture Clash in AmeriCCa, “Radio Mambo” and “The True History of Coca-Cola in Mexico.” Other Rep veterans in the company are Mike Genovese and John Padilla. Making impressive San Diego Rep debuts are Richard Trujillo and Bobby Plasencia. Siguenza and Trujillo portray twin brothers Gabriel and Gilbert Garcia, nicknamed Water and Power by their father (Padilla), who digs ditches for the City of Los Angeles. In flashbacks, he teaches them pugnacity and also instills in Gilbert, the elder by a lightning flash, an obligation to protect his less resourceful brother. Most of the action takes place at the Paradise Motel on Sunset Boulevard, where Gilbert/Power, a drugging and corrupt cop, is holed up after offing a just-released parolee. His informant and gofer is the wheelchair-bound Norte/Sur (Plasencia), part thug, part philosopher, poet, artist and seer. Norte/Sur has texted Gilbert, now a state senator, of his brother’s plight. Gilbert comes running, willing to do anything to save his bro. Genovese portrays the menacing Fixer, who maybe does and maybe does not. Other characters are played by Arturo Medina and Marc Alexander Gonzalez, who portray the Garcia brothers as children. Poetic and poignant, the work allows — through this flesh-and-blood familia — a deeper glimpse than one normally gets at the cinema. Sometimes motivations and even outcome are not clear, and there are at least three sputtering endings, before the final scene between Norte/Sur and Gilbert. One departs feeling as if one has witnessed a Greek tragedy East L.A. style. Hopefully, Montoya will tighten and tinker with the narrative arc of his flawed but important play (reportedly soon to be a film) during its San Diego run. “Water & Power” continues at 7 p.m. Wednesdays and Sundays, 8 p.m. Thursdays through Saturdays and 2 p.m. Sundays through Nov. 16. For tickets ($25-$53), visit www.sandiegorep.org or call (619) 544-1000.