Luis Valdez has dusted off a chunk of history and turned it into a vibrant, passionate gem.

All in the Family: Luis Valdez''s sons--Kinan, Lakin and Anahuac--star in their father''s play, Mundo Mata, about intrigue and dirty dealings during the UFW movement in the ''60s.

Mundo Mata, written and directed by Luis Valdez and now playing at El Teatro Campesino in San Juan Bautista, is a dramatic tour de force. It returns the company to its agit-prop roots--as well it should.

Written in 1976 about the 1973 grape strike, Mundo Mata had a brief tour through Texas and the Midwest before Valdez set it aside. Its problems, according to Valdez, were twofold: it dealt with the attempted assassination of United Farm Workers legend Cesar Chavez--still alive and well at the time--and it was in first draft form and needed attention.

Fast forward to 2001. Valdez brings Mundo Mata out of storage and polishes it. He lends his more than 36 years of experience in film and theater to the play and casts two of his three sons as the leads. Given the dimension added by the intervening years as well as Chavez''s death, Mundo Mata reaches for mythological status as it pits violence against non-violence, brother against brother.

Set in the fictional Central Valley town of Burlap, Mundo Mata revolves around the grape strike as it affects the lives of the two Mata brothers: Bullet and Mundo. Bullet--a nickname acquired as a kid fter outrunning his pursuing brother--is the younger sibling who''s finished college and returned to Burlap to help organize farm workers. Mundo, short for Raymundo, did a tour of Vietnam and participated in the My Lai massacre, an indelible experience that left him with a façade of angry anguish--and a penchant for violence.

Kinan Valdez gives breadth and a hungry fury to Mundo. He successfully captures the nuances of the sharp but ravaged Chicano as he tries to feebly piece together a sense of power in a world gone mad. Living with his mother, Doña Lola (ably played by Estrella Esparza), a dying woman who desperately clings to her rage and resentment, Mundo tries to turn Burlap into his own private version of Vietnam with himself at the top of the dung heap.

Accompanied by his terrific sidekicks Greñas and Huesos (Raul Sabino Cardona as Greñas is particularly noteworthy), Mundo seethes and swaggers his way from one crisis to the next, fomenting violence and waging a one-man campaign against humanity.

It''s a part that, in any other hands, could easily succumb to cliché and melodrama. But neither surfaces thanks to Luis Valdez''s crisp script and Kinan Valdez''s superb portrayal. Instead, we are witnesses to the disintegration of a man as he is tormented by memory and personal demons: a haunted, brilliant relic of the ravages of war.

Mundo''s foil and counterpart to all the violence is his baby brother Bullet. Educated and a Chavez devotee, Bullet is committed to the farmworkers'' cause, using non-violence and organization as his tools.

Lakin Valdez is competent as Bullet. A Teatro player since he was a tot, Lakin has plenty of dramatic presence and technical skill and his opening monologue gives a strong sense of place to the play. But his portrayal of Bullet is somewhat unmoored, floating just below the surface, where there are brief glimpses of his motivation.

Other supporting characters-- notably Sheriff Barnes and Guera, the brothers'' sister--are just this side of believable, tending toward caricature instead of nuanced participants in the drama. But Daniel Valdez lays down the aces as Tapon, fusing the best of commedia del''arte with the culture of Mexican theater to lend humor and pathos to his role.

Mundo Mata blends Spanish and English throughout the text, and English-only speakers will miss some of the asides. This shouldn''t be a deterrent. Valdez has successfully remounted a bit of history that is well worth re-visiting. And thanks to the talents of his predominantly stellar cast, Mundo Mata roils with a social conscience that''s in short supply in contemporary theater.