Soviet Union. Komitet gosudarstvennoĭ bezopasnosti

"The constellation of Russian connections circling around Planet Trump is quite extraordinary," says Guardian reporter Luke Harding. His new book is Collusion.

Former Russian master spy Sergei Tretyakov and journalist Pete Earley reveal secrets of espionage in America after the fall of the Soviet Union. Tretyakov ran Russia's post-Cold War spy program — but also worked as a double agent with the FBI before his defection in 2000.

Historian Christopher Andrew is the author of the new book "The Sword and the Shield: The Mitrokhin Archive and the Secret History of the KGB" (Basic books). The book is based on the documents smuggled out of the KGB archives by Vasili Mitrokhin, who worked for 30 years in the foreign intelligence archives of the KGB. In 1972 he began making notes and transcripts of the archives which he then smuggled out daily and hid. He defected to Britain in 1992.

Writer David Wise. He's written extensively on intelligence and espionage. His new book is "Molehunt: The Secret Search for Traitors that Shattered the CIA," (published by Random House) about the CIA's search for Soviet spies within in their own ranks.

Commentator David Gurevitz checks out some rumors about the KGB in the wake of the collapse of the Soviet empire. He's the author of "From Lenin to Lennon."

Journalist Hedrick Smith. He's the host of the new PBS series, "Inside Gorbachev's U.S.S.R." Smith won the Pulitzer Prize for his reporting from the Soviet Union in the 70's. His book, "The Russians" was a bestseller. He's now writing another book on Russia, "The New Russians."

Journalist David Wise. His new book, The Spy Who Got Away, is the story of Edward Lee Howard, the CIA agent who divulged secrets to the Russians and then eluded an FBI dragnet to flee to the Soviet Union. The book is based on six days of interviews with Howard in Budapest and reveals a CIA coverup of suspicions about Howard's character and the agency's refusal to share the information with the FBI's counterintelligence division. Wise, a former Washington bureau chief for the New York Herald Tribune, has written extensively on espionage.

Journalist Arnaud de Borchgrave co-wrote a spy-thriller novel called The Spike, which draws on his experience as a foreign correspondent. He talks about the role intelligence agencies often play in the world of journalism.