How did the government come to spy on millions of Americans? In FRONTLINE’s “United States of Secrets,” a two-part series from Michael Kirk and Martin Smith premiering May 13 and 20, FRONTLINE tells the inside story of the U.S. government’s massive and controversial secret surveillance program—and the lengths they went to trying to keep it hidden from the public.

How did the government come to spy on millions of Americans? In FRONTLINE’s “United States of Secrets,” a two-part series from Michael Kirk and Martin Smith premiering May 13 and 20, FRONTLINE tells the inside story of the U.S. government’s massive and controversial secret surveillance program—and the lengths they went to trying to keep it hidden from the public.

There are roughly 2.3 million people behind bars in the U.S., with a disproportionate number coming from a few city neighborhoods. More than two years in the making, “Prison State” takes an intimate look at the cycle of incarceration in America, and one state’s effort to reverse the trend. “Prison State” premieres Tuesday, April 29 on PBS and at pbs.org/frontline.

People think isolation is what drives some prisoners crazy--but FRONTLINE found, it might actually be the noise.

Former warden Gary Henman on how a 23-year prison lockdown began at Marion federal prison, which helped set a precedent for the use of solitary confinement in U.S. prisons today.

Former warden Gary Henman on why the lockdown at Marion federal prison was necessary to protect the staff and even the inmates. The staff was demoralized after the murders of two prison guards and needed new tools to help maintain control.

Former warden Gary Henman on why he decided to ease restrictions on some Marion inmates, in what would come to be called the "Marion model" adopted by supermax facilities operating today.

Even in solitary, inmates find ways to smuggle contraband from cell to cell. In Solitary Nation, premiering Tuesday, April 22 on PBS and at pbs.org/FRONTLINE, FRONTLINE brings viewers inside Maine's maximum security prison, where a new warden is trying to reduce the number of prisoners in solitary.

It was once believed solitary confinement would reform misbehaving prisoners, turns out it may push them to the brink of insanity. In Solitary Nation, premiering Tuesday, April 22 on PBS and at pbs.org/FRONTLINE, FRONTLINE takes you inside Maine's maximum security prison, where a new warden is trying to move inmates out of solitary, which isn't as easy as you might suspect.

Former warden Gary Henman says inmates hate isolation, which is why it works for all but the mentally ill or seriously emotionally disturbed.

Former warden Gary Henman on his strategy at Marion to keep the worst inmates in isolation. "We would take these so called rotten apples, put them together. If they spoiled each other, at least to allowed the other facilities to be safe, secure," he said.

About 80,000 Americans are held in solitary confinement on any given day. In “Solitary Nation,” premiering Tuesday, April 22 on PBS and at pbs.org/frontline, FRONTLINE deeply examines the use and impact of this controversial practice—and takes an unprecedented look at life inside solitary at a maximum security prison in Maine.

Former warden Gary Henman on how his Marion model worked to modify inmates’ behavior. If they followed the rules, they earned more privileges.

Former warden Gary Henman defends the Marion model from criticism that the long-term isolation violates inmates’ constitutional rights.

FRONTLINE presents an unforgettable portrait of lives forever changed by tuberculosis, once thought to be a disease of the past.

At just 12-years-old, Nokubheka has already lost her mother to TB. Now she has been diagnosed with strain of the disease herself. "I think anybody can have TB," she tells FRONTLINE. "It is not choosy.”

“Secrets of the Vatican,” a special, 90-minute FRONTLINE presentation premiering Feb. 25, tells the epic, inside story of the collapse of the Benedict Papacy—and illuminates the extraordinary challenges facing Pope Francis as he tries to reform the powerful Vatican bureaucracy, root out corruption, and chart a new course for the troubled Catholic Church and its 1.2 billion followers.