Best known as a correspondent for "The Daily Show with Trevor Noah," stand-up comic Roy Wood Jr. is noted for satire that confronts the tough topics head-on. His new hour-long special for Comedy Central, "Imperfect Messenger," takes on everything from race and police reform to mass shootings and celebrity activism. Here is Roy Wood Jr. talking to Hari Sreenivasan.

We take a look at how one man shook the foundations of American democracy by tearing up the Constitution in a time of deadly peril. Harvard Law professor and Bloomberg columnist Noah Feldman's new book "The Broken Constitution" examines President Lincoln’s thought processes as he rewrote the rulebook and grappled with challenges from both political rivals and passionate abolitionists.

Tsedale Lemma is an Ethiopian journalist and the founder of the Addis Standard magazine. She has testified before the House Foreign Affairs Committee and has written for The New York Times. She joins the program to discuss what could come next for her country.

The father and daughter duo Chase and Tokata Iron Eyes were key figures in the 2016 protest against the Dakota Access Pipeline. They speak with Hari Sreenivasan about how their tribe’s demonstrations moved the dial and why their fight for indigenous justice continues.

What is it like to walk alongside history? As Hillary Clinton's top aide, Huma Abedin knows all too well. She usually prefers to stay out of the spotlight, but Abedin’s private life became a public scandal around the actions of her then-husband, Anthony Weiner – a scandal that some say ultimately cost Clinton the presidency in 2016.

In a major shift today, House Speaker Nancy Pelosi said she would reverse course and include paid family and medical leave in the social spending package. One of the provision’s key backers is New York Senator Kirsten Gillibrand. She speaks with Michel Martin about how she plans to convince fellow Senator Joe Manchin to get on board.

The first major election since Biden took office has fueled speculation that the Democrats’ razor-slim congressional majorities are in danger, while Biden’s spending bills still hang in the balance. Those bills, says Janet Yellen, are critical for economic growth. The treasury secretary and former chair of the Federal Reserve is attending the climate summit, and joins the show from Glasgow.

Are last night’s election results an early verdict on the Biden presidency? That’s how some are framing it. The president won VA easily last year, but now voters have chosen a Republican governor, while the race in NJ was far closer than expected. To dig into all this, Bianna speaks with former Mitch McConnell advisor Scott Jennings and political analyst Larry Sabato.

Back in Glasgow, youth activists are urgently reminding world leaders of their responsibilities to future generations. Ugandan campaigner Vanessa Nakate has become a superstar for her work in the movement for climate justice, a struggle that she depicts in her new book, "A Bigger Picture: My Fight to Bring a New African Voice to the Climate Crisis." She joins the show from Glasgow.

Director of the National Institute of Health Dr. Francis Collins, who has guided the U.S. through the COVID-19 crisis, recently announced he will step down after 12 years and three presidents. He tells Walter Isaacson how vaccine resistance and conspiracy theories presented one of his most difficult challenges as director.

A U.S.-led alliance at the COP26 summit has pledged to cut methane emissions by 30% by the end of the decade. The pledge is non-binding, but it is being touted as an early win for this climate summit and for its host -- British Prime Minister Boris Johnson. He sat down with Christiane for an exclusive interview from the summit.

The urgency at this year's COP26 summit is palpable, and few are more aware of this than former Secretary of State and President Biden's climate tsar John Kerry. Kerry sits with Christiane to discuss efforts to lower carbon emissions in India and China.

At the COP26 summit today, there was a passionate plea from Barbadian Prime Minister Mia Mottley. Her tiny nation is among those bearing the brunt of climate change. She’s calling on rich nations and major polluters to step up and help nations like hers. Mottley joined Christiane for a frank discussion in Glasgow after she addressed the plenary of national leaders.

Scotland's First Minister, Nicola Sturgeon, finds herself hosting top officials and climate leaders from all corners of the globe as they descend on her country. There will no doubt be a lot of talk. Will it translate into action? The Scottish leader joins Christiane to explain why she feels cautiously hopeful.

Global leaders are gathered at the COP26 summit in Glasgow this week to collaborate in the fight against climate change. Among them is European Union Commission President Ursula von der Leyen, who says the success of the conference hinges on the creation of concrete proposals that will limit global warming to 1.5 degrees Celsius.

Last Thursday's House Oversight Committee hearing featured testimony from six major fossil fuel companies and trade associations about their part in climate change, and whether they misled the public about the reality of the crisis. Rep. Ro Khanna helped lead this historic hearing. He joins Hari Sreenivasan to explain the disconnect between what these companies say and what they do.

As the pandemic eases in some parts of the world, we’re seeing the so-called “great resignation:” 20 million people in the U.S. have quit their jobs since April, according to federal statistics. Jennifer Moss explains this phenomenon in her new book "The Burnout Epidemic," and speaks with Michel Martin about why this is a cultural, rather than an individual, problem.

President Biden and the U.N. Security Council are calling for Sudan's civilian government to be restored, while both the State Department and the World Bank have suspended aid to the country. For more on this, Bianna speaks with Mohanad Hashim, a freelance Sudanese journalist who has just returned to London.

President Biden is back in the global spotlight, meeting with G20 leaders -- and Pope Francis in Rome -- prior to the U.N. climate summit in Glasgow next week. What is the current state of the president’s domestic agenda -- and how could it impact American diplomacy? Experts Mo Elleithee and Mark Landler join the program to offer their analysis.

Today, President Biden met with the Pope at the Vatican – his fourth face-to-face meeting with Pope Francis. The 90-minute discussion covered a wide range of issues, including climate and inequality. One who understands the significance of the meeting is Cardinal Blase Cupich, the Archbishop of Chicago.