Manhunt: Boston Bombers

Immediately after the Boston Marathon bombing in April 2013, amateur detectives took the Internet chat rooms to try to find the culprits, looking for details in photographs uploaded to the sites that could point to the guilt of potential suspects.

In April 2013, chaos erupted in Boston near the finish line of one of the world's oldest and most prestigious marathons. It was the worst terrorist attack on the United States since 9/11 and led to one of the most extensive and public manhunts in American history. Now, as the one-year anniversary approaches, National Geographic Channel presents a special two-hour event, Inside the Hunt for the Boston Bombers.

The history of the Boston Marathon from its humble origins starting with only 15 runners, to the first female runners, through the tragedy in 2013, and ultimately the triumph of 2014.

A retrospective on the Boston bombing.

In 1980 Jay Helgerson shocked the world, becoming the first person to run a marathon a week for a year – each race completed in under three hours. For the last ten years, his daughter, filmmaker Alexandra Helgerson, followed him with a camera in order to understand the eccentric man who raised her. What she gets are his projected anxieties, his struggles with physical age and emotional distress, all while he endlessly trains for the Boston Marathon. But as Jay trains, the film is nearly derailed by Alexandra’s encounter with a life threatening illness. Ultimately, AGE GROUP WINNER is an affirmation of the will to live.

This Canadian made comedy/drama, set in Hamilton, Ontario in 1954, is a sweet and - at times - goofy story that becomes increasingly poignant as the minutes tick by. It's the fictional tale of a wayward 9th grader, Ralph (Adam Butcher), who is secretly living on his own while his widowed, hospitalized mother remains immersed in a coma. Frequently in trouble with Father Fitzpatrick (Gordon Pinsent), the principal of his all-boys, Catholic school, Ralph is considered something of a joke among peers until he decides to pull off a miracle that could save his mother, i.e., winning the Boston Marathon. Coached by a younger priest and former runner, Father Hibbert (Campbell Scott), whose cynicism has been lifted by the boy's pure hope, Ralph applies himself to his unlikely mission, fending off naysayers and getting help along a very challenging path from sundry allies and friends.

A victim of the Boston Marathon bombing in 2013 helps the police track down the killers while struggling to recover from devastating trauma.

In the aftermath of an unspeakable act of terror, Police Sergeant Tommy Saunders joins courageous survivors, first responders and investigators in a race against the clock to hunt down the Boston Marathon bombers before they strike again.

A rousing tale of the Korean athletes who ran the 1947 Boston International Marathon, the first international marathon held since World War II.

A fictional film about a runner's relationship with his sister and brother as he tries to qualify for Boston.

In this ultimate guide to Scandinavia travelers Megan McCormick, Ian Wright and Neil Gibson explore Denmark, Sweden, Norway, Lapland, Finland and the Baltic States. From enjoying a traditional Viking festival to crossing the Arctic Circle into Lapland for dinner with reindeer herders to a visit to the capital of Lithuania, Vilinus, and the Midsummer Night Festival in Kernave, these hosts will introduce the viewer to a variety of sites and attractions during their Scandinavian tour.

Henry Jaglom discusses the influence of such filmmakers as Fellini and Cassavetes on his work, and the theatrical nature of "A Safe Place."

The inside story behind the hunt for ISIS poster boy "Jihadi John" by the US and British military and intelligence services. An interrogation of the twisted worldview espoused by ISIS and its propaganda machine which was operated by "Jihadi millennials" who turned social media sites such as Twitter and YouTube into recruitment platforms.

Jean-Claude van Damme, Sheldon Lettich and more discuss the 1991 film "Double Impact" from inception to reception.

Laganja Estranja teaches a dance class in London followed by a performance at the West 5.

A look at the varied new ways Americans are choosing to both find meaning and celebrate life as it comes to an end.

When Women Kill is a poignant documentary exploring the shocking violence that seven women fell victim to at the hands of men. The program profiles the battered women who speak frankly about the cruel abuse, threats, and fears, and the overassertive men who led them down a one-way path to death and destruction. The film features in-prison footage, including a segment depicting a confession by a follower of the notorious Charles Manson, Leslie Van Houten, who was convicted of two killing sprees and committed to life in prison.

This is a full-length documentary honoring the life and work of American composer and artist John Cage. Cage is considered one of the most influential composers of the 20th century. This documentary features interviews with various personalities from different fields as they introduce us to the life and work of this great American artist.

Bas Jan Ader rides his bike into a canal in Amsterdam.

A brief documentary about Dorothea Tanning with gothic flourishes.