Heroes alive and dead, real and cinematic, take center stage on Memorial Day. Gen. David Petraeus offers commentary during the “War Heroes” marathon on AMC, including eight combat films, beginning with “The Devil’s Brigade” (8:30 a.m.). Highlights include director Sam Fuller’s 1980 epic “The Big Red One” (4:15 p.m.).

• The Fox Movie Channel will also air an all-day marathon of combat films, most notably “Patton” (8 p.m., FMC). The network will also salute the work of the USO (United Services Organizations) and air short USO featurettes between films.

• “Hallowed Grounds” (9 p.m., PBS, check local listings) visits four overseas military cemeteries from World Wars I and II and includes archival footage of the battles in Europe that cost so many American lives.

• “Uncommon Courage: Breakout at Chosin” (7 p.m., Smithsonian) recalls the valor of a Chinese-American soldier who overcame prejudice to lead U.S. Marines as they resisted a Communist Chinese onslaught during the Korean War.

• The 2009 documentary “Who Will Stand” (7 p.m., Documentary Channel) looks at how recent Iraq War veterans are adjusting to civilian life and the difficulties many face. One expert cited here contends that more Americans soldiers will die from self-inflicted wounds than died in combat.

• Turner Classic Movies celebrates Clint Eastwood’s birthday with a 24-hour Clint Eastwood film festival, starting with “The First Traveling Saleslady” (5 a.m., Eastern). A bomb from 1956, the film starred Eastwood as Carol Channing’s boyfriend! Eastwood’s half-century career as an actor, director and producer gets a once-over on “The Eastwood Factor” (9:30 p.m., TCM), narrated by Eastwood’s “Unforgiven” co-star Morgan Freeman.

Tonight’s other highlights

• A farmer’s fertilizer raises eyebrows on “Lie to Me” (7 p.m., Fox).

• Vegas- and Hollywood-bound on “The Bachelorette” (7 p.m., ABC).

• A minor case takes on major players on the repeat pilot episode of “Good Guys” (8 p.m., Fox).

• A vagabond stands accused of an heiress’s murder on “CSI: Miami” (9 p.m., CBS).

• A murdered man’s body bears graphic evidence on “Law & Order” (9 p.m., NBC).

• The raucous and strenuously irreverent FX series “It’s Always Sunny in Philadelphia” (8 p.m., through 10 p.m.) moves to Comedy Central in repeat mode.

• Fresh from winning “The Celebrity Apprentice” and very public health scares, “Bret Michaels: Life As I Know It” (9 p.m., VH1) follows the rocker/reality TV star at home and on tour.

• Six fathers-in-waiting receive remedial training on “Dad Camp” (9:30 p.m., VH1).