With the fifth anniversary of 9-11 just weeks away, the architect of the terror attack remains at large and remains a mystery. Christiane Amanpour hosts “In the Footsteps of Bin Laden” (8 p.m., CNN), a two-hour biography of Osama bin Laden, featuring interviews with 21 friends, colleagues, teachers and reporters who have known the enigmatic figure at different stages of his life.

Amanpour travels to four continents to present this narrative biography. One reporter remembers coming upon bin Laden in Afghanistan during the war against the Soviet Union. They politely discussed politics and religion for a half hour, and then he was dismissed with the warning, “If I see you again, I will kill you.”

A boyhood friend recalls a very different bin Laden: He was a shy kid and a so-so student, not given to violence or fights. Their memories include endless hours of television, including American cowboy movies and Hong Kong martial-arts films.

Along the way, we’re given not only an outline of bin Laden’s life story but the evolution of radical Islam and its growing hatred for the West.

¢ The new documentary series “Two-a-Days” (9:30 p.m., MTV) will spend eight episodes with a championship high school football team and follow the players as they try to balance a grueling twice-a-day practice schedule with schoolwork and their social and family lives.

“Two” chronicles the 2005 football season of the Hoover, Ala., Buccaneers, a team chasing its fourth state championship in five years. Hoover treats football with religious devotion.

“Two” does a good job of capturing the pressure-cooker atmosphere of playing football in this high-stakes environment.

But its focus on the social elite of a championship team also deprives the documentary of the Cinderella-story aspect that drives so many interesting sports dramas. Think “Hoosiers,” “Rudy” and any number of films about the 1980 Olympic hockey upset.

¢ Another fishbowl documentary series, “The Hill” (8 p.m., Sundance) follows the young, driven and generally overworked staff of a Florida congressman on Capitol Hill. “The Hill” will air Wednesday nights for six episodes.

¢ Kevin Nealon (“Weeds”) and his wife, Susan Yeagley (“Curb Your Enthusiasm”), host “World’s Funniest Commercials” (8 p.m., TBS), an annual roundup of amusing advertising spots from around the globe.