Neal Katyal is a former acting U.S. Solicitor General, and has argued at the Supreme Court nearly forty times. His new book is unequivocal in its argument, right from the title: “Impeach: The Case Against Donald Trump”. Katyal joins the program to outline why he thinks it’s a clear-cut case of high crimes and misdemeanors.

Dangerous times call for dangerous women—so says media legend Pat Mitchell. She rose through the ranks to become head of films at CNN, and then the first female president of PBS. A lifelong advocate for women and girls, Mitchell launched TEDWomen in 2010, and her latest book is called “Becoming a Dangerous Woman."

In an era of political turmoil, one author has opted for humor to get his message across, as he examines America’s political culture wars. Joel Stein is a former writer for Time Magazine and his new book, “In Defense of Elitism,” offers a sharp and witty take on why he thinks elitism is so important to fight the rise of populism. He sits down with Walter to discuss this subject.

The new film "The Report" tells the true story of a Senate investigation that exposed the CIA’s use of torture following 9/11, and how Senator Dianne Feinstein defied the Obama White House to expose wrongdoing at the highest levels. Annette Bening stars as Feinstein, and she joins the program to discuss the film, her career and friendship with the late John McCain.

With Democrats hoping to vote on articles of impeachment before Christmas, the political temperature in the U.S. looks set to keep rising. They say the evidence of serious presidential misconduct is overwhelming, but President Trump’s defenders are only digging in, responding with conspiracy theories, disinformation and distortion. Doris Kearns Goodwin joins Christiane in New York to discuss.

Harvard Law School Professor and former Dean Martha Minow has taught generations of lawyers – including former President Obama – about the power of the law and how a sentence can best match a crime. She sits down with Michel to discuss how the American legal system, whose rate of incarceration is the highest in the world, could use a little compassion.

Journalist Maria Ressa is CEO of Rappler, a news site in the Philippines, where she fearlessly reports on the brutal realities of President Duterte’s infamous "war on drugs," which has left a trail of bodies in its wake. Now Ressa herself is in the firing line, facing criminal charges from the government. She joins Christiane to talk about her reporting and the importance of a free press.

Olafur Eliasson is an Icelandic artist who takes the climate crisis extremely seriously, and his new exhibit at London’s Tate Modern is taking the art world by storm. He takes a break from hanging another show – his photos of the devastating impact on glaciers over 20 years – to speak with Christiane about giving people a positive experience by connecting them with nature.

Lesley Stahl has been a familiar face on "60 Minutes" for nearly three decades, and she secured the first interview with then President-elect Trump after the 2016 election, which made headlines around the world. Stahl sits down with Walter to discuss Trump's attacks on the press, the current impeachment hearings and how the Watergate scandal changed her career and the course of American history.

Today, Benjamin Netanyahu became Israel's first sitting prime minister to face a criminal indictment, with the attorney general announcing charges of bribery, fraud and breach of trust. Netanyahu is being accused in three different corruption cases, but denies any wrongdoing. Investigative journalist Ronen Bergman joins the program to explain what this means for Netanyahu and Israel.

The Democrats had their latest debate last night, with the candidates facing an all-female panel of moderators. Veteran former senator Russ Feingold joins the program to assess last night's events.

Prince Andrew has now stepped back from all public duties after giving an interview to the BBC, wherein he addressed his friendship with Jeffrey Epstein and denied allegations he had sex with an underage woman. The interview backfired spectacularly, resulting in the prince issuing a further statement to clarify his position. Christiane assesses this scandal with Dickie Arbiter and Afua Hirsch.

Treason, bribery, high crimes and misdemeanors: four things which are integral to an impeachment process, and which Cass Sunstein can explain better than most. He is a Harvard Law Professor who also served as a White House administrator under President Obama. Walter sits down with Sunstein to find out his take on the impeachment hearings and how "Star Wars" relates to today's politics.

In bombshell testimony today on Capitol Hill, key impeachment inquiry witness Ambassador Gordon Sondland made it crystal clear he was working at the direction of President Trump as he tried to get Ukraine to investigate the Bidens and the 2016 election. To analyze, Christiane speaks with former White House counsel Bob Bauer, and Evelyn Farkas, the former Russia expert at the Department of Defense.

The U.N. warned last year that we barely have a decade to avoid the worst consequences of climate change, an emergency due in no small part to major fossil fuel companies. Dutch activist Mark van Baal wanted oil giants to change their policies, so he bought shares in one of the biggest oil companies in the world, Shell, and became a so-called activist investor, pushing for change from the inside.

Imelda Marcos, the former first lady of the Philippines, is known for the ruthless dictatorship she and her late husband headed for two decades, massively enriching themselves in the process. Director Lauren Greenfield and former investigator of the Marcos family, Andy Bautista, join Alison to discuss "The Kingmaker," a new documentary about the larger-than-life Imelda.

Today, impeachment hearings in Washington entered a critical stage. Eight key witnesses from the Trump administration are defying White House orders and taking the stand this week, with White House Ukraine expert Lt. Col. Vindman and Vice President Pence's national security aide Jennifer Williams kicking off proceedings. Christiane discusses Tuesday's events with Chris Ruddy and Susan Glasser.

Daria Kaleniuk is one of Ukraine's most respected independent corruption fighters, having spent years taking on officials seeking to abuse their authority. She joins the program from Ukrainian capital Kyiv to discuss corruption, the impeachment inquiry and Ukraine-Russia relations.

Professor S. James Gates has spent his career pioneering modern physics and diversity in science. His most recent book, written with novelist Cathie Pelletier, is about how scientists proved Einstein's groundbreaking theory of relativity all those years ago. Walter sits down with Gates to find out just how they did this, and how his own upbringing played such a pivotal role in his success.

As a climate scientist, educator, and lead author for U.S. national climate assessments, Katharine Hayhoe is devoted to exposing diverse—sometimes suspicious—audiences to the cataclysmic events happening right before our eyes as a result of climate change. She joins the program to explain how to convince people and what changes are needed.