Slick Willie

Relive the scandal that rocked the nation 20 years ago in "The Lost Tapes: Clinton Impeachment," a documentary that uses news excerpts and secretly recorded phone calls to take you back to a time when an intern named Monica Lewinsky took center stage. The clips of Donald Trump defending Bill Clinton are downright eerie.

8 p.m., Smithsonian Channel

The social network

There's a bizarre scene near the beginning of "The Facebook Dilemma" in which Mark Zuckerberg tries to pitch his newish social media network to a near-empty classroom. As this two-part "Frontline" documentary shows, demand for the young entrepreneur would soon increase exponentially, as would the challenges.

8 p.m., TPT, Ch. 2

The land of Oz

Kristin Chenoweth and Idina Menzel reunite for "A Very Wicked Halloween: Celebrating 15 Years on Broadway" with guests Ariana Grande and Pentatonix. "Wicked" may not technically have had as big an impact as "Hamilton" — but try telling that to the girls belting out "Defying Gravity" in their bedrooms.

9 p.m., KARE, Ch. 11

Neal Justin