“Secrets of the Dead” (7 p.m., PBS, check local listings) presents “Lost in the Amazon,” a tale that seems straight out of “Indiana Jones.” In fact its subject, Col. Percy Fawcett, an explorer in search of Lost Cities of Gold who vanished — some say was murdered — in 1925, probably inspired the kinds of pulp paperbacks and Saturday-movie serials that would become the template for the character played by Harrison Ford.

A product of the Late Victorian era, Fawcett combined the imperial derring-do of the period with occult eccentricity and faith in the mystic. He believed that the Amazon not only hid legendary cities but also was the source of powerful psychic forces. He never found them. But “Secrets” ponders several theories about his disappearance and unearths new evidence of Amazonian population centers unlike any city in the known world.

• You can’t say ABC isn’t giving folks a chance to sample “Happy Endings” (ABC, TV-14). The network aired two consecutive episodes last Wednesday and will do so again tonight. “Endings” didn’t exactly grow on viewers last week, shedding a large percentage of its audience over the space of 60 minutes.

On tonight’s two episodes of “Happy Endings,” Jane and Brad think about making new friends (9 p.m.), and the gang suggest that Max’s parents need to know about his sexual identity (9:30 p.m.).

• A year after the BP oil spill in the Gulf of Mexico, the documentary “Saving Pelican 895” (8 p.m., HBO) recalls the heroic and painstaking efforts to save wildlife blighted by the environmental disaster.

The state bird of Louisiana, the brown pelican was all but driven from the region because of pesticides in the ecosystem. The chemical pollution rendered brown-pelican eggs too flimsy to hatch. Tireless efforts to reintroduce the brown pelican to Louisiana finally paid off, and in November 2009, the bird was removed from the endangered-species list for the first time in 45 years. Fewer than six months later, the BP spill filled the gulf with oil, killing thousands of birds.

“895” profiles some of the remarkable people who dedicate their time and skills to saving imperiled wildlife.

• “Inside the Muslim Brotherhood” (9 p.m., National Geographic) examines a powerful political organization at the center of recent unrest and revolution.

Tonight’s other highlights

• The top seven perform on “American Idol” (7 p.m., Fox) without Paul McDonald, voted off last week.

• Mitchell and Cameron ponder the unthinkable and contemplate naming a guardian for Lily on “Modern Family” (8 p.m., ABC).

• “Jesus: The Lost 40 Days” (8 p.m., History) examines tales from the New Testament.

• On two episodes of “Law & Order: Special Victims Unit” (NBC), a repeat victim needs encouragement (8 p.m.), human trafficking (9 p.m.).

• A cry for help on “Breaking In” (8:30 p.m., Fox).

• Children go missing in Cleveland on “Criminal Minds: Suspect Behavior” (9 p.m., CBS).

• Raylan realizes a killer may have more than one target on “Justified” (9 p.m., FX).