Mention important Mexican muralists of the past century and three names come to mind: Diego Rivera (1886-1957), Jose Clemente Orozco (1883-1949) and David Alfaro Siqueiros (1896-1974). Rivera is certainly the best known, but "Orozco: Man of Fire," which debuts at 9 p.m. Wednesday on WQED, should help to ease that imbalance.

The program will be followed at 10 p.m. by "Rivera in America," which originally aired in 1988.

They're both part of PBS's "American Masters" series. Ostensibly the artists qualify because of the significant work each did in the United States; the inspiration they provided for Franklin Delano Roosevelt's WPA program, which employed artists across the country to paint murals; and their influence upon many American artists. (And, of course, Mexico is part of the Americas.)

Viewing the two programs concurrently affords the opportunity to compare artists.

Their similarities include activist political expression, the ability to represent complex scenarios on a grand scale, a grappling with positive and negative consequences of technology as it became more prominent at the turn of the century, dynamic use of color and form, and empathetic representation of laborers. Each also had turbulent personal lives, some of that the consequence of charged libidos.

Orozco particularly suffered a number of setbacks, including the death of his father while he was studying at university, and the loss of his left hand while preparing fireworks to sell in the shop that he subsequently opened to help his impoverished family. Such events add to the emotional weight of the program, but that is also a production choice.

The programs were made almost 20 years apart and reflect changing tastes in film aesthetics as well as in presenting biography. Both are enjoyable to watch and are packed with information. Film clips and photographs of the artists, frequently at work, are especially captivating.

The Rivera film is a fairly straightforward documentary about the cosmopolitan artist. The Orozco film has a lyrical component, visually and in the way it probes the psychological state of its more insular subject.

Both created artworks, at home and in the States, that stirred controversy in the early decades of the century, and exceptional examples from both countries are shown.

Among these are Rivera's extraordinary 1932 tribute to labor which survives on the walls of the Detroit Institute of Arts, not far from Ford's Rouge Plant which at the time was the world's biggest industrial complex.

Also addressed is the mural that Nelson Rockefeller commissioned in 1933 for the newly constructed Rockefeller Center. The mural was destroyed when Rivera refused to cover up a portrait of Lenin he'd included. (Rivera had the final say when he re-created the mural in Mexico, adding a portrait of John D. Rockefeller Jr., and, directly above him, oversized syphilis bacteria.)

After 1941, Rivera did not return to the United States. He has enjoyed renewed interest in recent years because of a cult-like following of his third wife, artist Frida Kahlo, who divorced but later remarried him.

Orozco earned his early reputation as a political cartoonist, addressing the horrors of the Mexican Revolution, which began in 1910, for an opposition newspaper. While his irreverence cost him commissions post-revolution, critics eventually would dub him the "conscience of his generation."

An early attempt to establish himself in the United States was not successful, but by the 1930s he would be championed by the administration of Dartmouth College when a mural the school commissioned met with opposition. Jackson Pollock declared his 1930 fresco "Prometheus," at Pomona College, Calif., the "greatest painting in North America."

But Orozco truly soared in Mexico, his apex the breathtakingly passionate murals that hover high above visitors to the Hospicio Cabanas, Guadalajara.

His last paintings, which his son Clemente calls premonitory, show an abstract, airy "Metaphysical Landscape" dominated by a black rectangle, "a window on the infinite which is unknowable, but it exists."

"This type of mysticism," his son says, "is the mysticism of Jose Clemente Orozco."

While a one-hour format requires a lot of distillation, one thing that does come across is that Orozco and Rivera are larger-than-life figures who have left behind a legacy of a similar scale to ponder and to enjoy.

To explore these and other "American Masters" subjects further, visit www.pbs.org/wnet/americanmasters.