See what can go wrong when police are faced with domestic violence allegations in their own ranks.

The National Football League, a multibillion-dollar commercial juggernaut, presides over America's indisputable national pastime. But the NFL is under assault as thousands of former players and a host of scientists claim the league has covered up how football inflicted long-term brain injuries on many players. In a special investigation, FRONTLINE and prize-winning journalists Steve Fainaru and Mark Fainaru-Wada of ESPN reveal the hidden story of the NFL and brain injuries, drawn from their forthcoming book League of Denial: The NFL, Concussions and the Battle for Truth (Crown Archetype, October 2013). What did the NFL know and when did it know it? What's the truth about the risks to players? What can be done? The FRONTLINE investigation details how, for years, the league denied and worked to refute scientific evidence that the violent collisions at the heart of the game are linked to an alarming incidence of early onset dementia, catastrophic brain damage, death, and other devastating consequences for some of football's all-time greats.

Examine the rise and rapid fall of Egypt's Muslim Brotherhood.

Since 1992, Bill Moyers has followed the story of two ordinary, hard-working families in Milwaukee — one black and one white — as they battle to keep from sliding into poverty. A remarkable portrait of perseverance, Two American Families raises unsettling questions about the changing nature of the U.S. economy and the fate of a declining middle class.

It's a central premise of the American dream: If you're willing to work hard, you can make a living and build a better life for your children. But what if working hard isn't enough to ensure success — or even the basic necessities of daily life?

This episode follows two ordinary families who have spent the past 20 years in an extraordinary battle to keep from sliding into poverty.

The film, a collaboration with veteran PBS journalist Bill Moyers, who has followed the Stanleys and the Neumanns over the years, raises unsettling questions about the changing nature of the American economy and the fate of a declining middle class.

Trace a teenaged rape victim's five-year odyssey through Pakistan's broken justice system.

Travel to the Jewish ghettos of Poland to hear the poignant recollections of child survivors.

Learn how fees, self-dealing and kickbacks profit Wall Street while imperiling our savings.

Witness the devastating effect of the religious feud that's shaping Syria's future.

Examine the life of Adam Lanza, the Newtown shooter, and the battle over gun laws and gun culture.

Investigate the secret history of Washington's failure to solve the country's debt and deficit problems.

Learn why Wall Street leaders connected to America's financial meltdown have escaped prosecution.

Examine President Obama's key decisions and the experiences that will inform his second term.

Examine the legacy of controversial former chancellor of Washington, DC, public schools, Michelle Rhee.