What is it like supporting a family on a minimum-wage salary? “Investigative Reports: Wage Slaves: Not Getting By in America” (8 p.m., A&E) takes a provocative look at a surprisingly large segment of American society.

According to the U.S. Bureau of Labor Statistics, nearly 20 percent of full-time workers can be classified as poor. One-third of the American work force earns between $7 and $8 an hour. Many cannot afford housing, health care or prescription drug coverage.

Best-selling author Barbara Ehrenreich went undercover as a minimum-wage earner while researching her book “Nickel and Dimed: On (Not) Getting By in America,” working as a waitress, a health care provider and a Wal-Mart cashier. She discovered an entire class of Americans who are working hard at several jobs every day but falling behind.

In an effort to be balanced, “Wage Slave” also talks with economists and columnists who argue that a higher minimum wage is not the answer to poverty, and that the very existence of a minimum wage tends to discourage companies from hiring the young, the poor and the unskilled. Another expert argues that poor people in America have televisions, microwaves and other amenities that are far beyond the reach of middle-class people in other countries.

Ehrenreich and others mourn the loss of what used to be called a “social contract” between labor and capital that encouraged the growth of a stable middle class. They also note that while the minimum wage has remained static (when adjusted for inflation), executive salaries have skyrocketed. More companies are following the model of McDonald’s and other fast-food outlets that treat their work forces as an entirely replaceable “cost” of doing business. They contend that such thinking may work for the corporate bottom line, but it has alienated millions of American workers, with an incalculable cost to their children, their schools and towns, and to society.

“Gods and Goddesses” (8 p.m., History) offers a layman’s guide to Greek mythology and its fascinating pantheon of squabbling deities. Mixing footage of Greek scenery, art and interviews with scholars and Greece’s deposed King Constantine, “Gods” examines the lingering influence of these 3,000-year-old legends. Terms like “Pandora’s box,” “Cassandra” and “tantalizing” come down to us from these fantastic stories that the ancients used to explain the mysteries of creation, the meaning of life and the cruel and fickle nature of fate.

“Behind the Music” (8 p.m., VH1) has profiled more than 170 dysfunctional rock stars since it debuted in August 1997. Now it celebrates itself with a fifth birthday party. Over the next six nights, “BTM” will look back at its most memorable moments, including Ozzy Osbourne’s dove snack, the late Lisa Lopes’ jealous act of arson and Leif Garrett’s tearful encounter with the man he paralyzed 20 years earlier.

Tonight’s other highlights

Clips from the first six seasons on a repeat of “Everybody Loves Raymond” (8 p.m., CBS) special.

Green Bay takes on Cleveland in a preseason game on “Monday Night Football” (8 p.m., ABC).

An elderly woman dies surrounded by cats on “CSI” (9 p.m., CBS).

“Saturday Night Live” comic Tracy Morgan performs standup on “Tracy Morgan: One Mic” (9 p.m., Comedy Central). Beginning Sept. 2, Morgan will be host for the half-hour stand-up series “Comic Groove.”

Cult choice

In the 1983 fantasy “Peggy Sue Got Married” (7 p.m., AMC) actor Nicolas Cage got to act a lot like Elvis as he wooed time-traveler Kathleen Turner. Now, Cage is married to Presley’s daughter. Maybe Cage should make a remake called “Lisa Marie Got Married.”