Tuning In

* 300 (8 p.m. HBO) - The Persian army wages war against the Spartans in an attempt to conquer ancient Greece in this 2007 action-packed adaptation of Frank Miller’s graphic novel. Gerard Butler, Lena Headey, David Wenham and Dominic West star in the epic drama, which chronicles the Spartans’ bloody struggle to retain Greece during the Battle of Thermopylae.

Sunday

* National Memorial Day Concert (8 p.m., WETA-Channel 26) - Oscar nominee and “CSI NY” star Gary Sinise hosts the annual program for the third time, airing live from the West Lawn of the Capitol. Tony Award winner Joe Mantegna (“Criminal Minds”) joins Mr. Sinise for this year’s event, which will pay special tribute to the veterans of World War II and the Korean and Vietnam wars and the memorials built in their honor. Actor and highly decorated World War II veteran Charles Durning also will be recognized for his bravery and sacrifice in a tribute to the “greatest generation.” An all-star lineup of dignitaries, actors and musical artists also will join the National Symphony Orchestra under the direction of Erich Kunzel.

* Recount (9 p.m., HBO) - The controversial 2000 presidential race is seen through the eyes of Ron Klain, Al Gore’s former chief of staff (two-time Oscar winner Kevin Spacey). A heavily made up Laura Dern plays Florida Secretary of State Katherine Harris.