Series Finale Time for Supergirl and Impeachment: American Crime Story

After six seasons, The CW’s Supergirl says goodbye tonight with one last battle between Kara Zor-El (Melissa Benoist) and Big Bad Lex Luthor (Jon Cryer). The two-episode finale also features the wedding of Alex (Chyler Leigh) and Kelly (Azie Tesfai), whose relationship formed the backbone of the superhero drama’s later seasons.

Also today: Impeachment: American Crime Story reaches its conclusion, Netflix dives into the world of used collectibles in Swap Shop, and HBO profiles snowboarding pioneer Jake Burton Carpenter. Here’s what’s new and noteworthy on TV this Tuesday:

Supergirl: Series finale. When a loved one is kidnapped by Nyxly (Peta Sergeant) and Lex (Jon Cryer), Supergirl (Melissa Benoist) joins forces with some familiar faces from the past to stop the supervillain for good. Meanwhile, Alex (Chyler Leigh) and Kelly (Azie Tesfai) prepare to walk down the aisle. Watch preview. 8:00 PM ET on The CW

Impeachment: American Crime Story: Limited series finale. After the Starr Report is released, President Bill Clinton (Clive Owen) is impeached. Also, Linda Tripp (Sara Paulson) faces the aftermath of her decisions, Monica Lewinsky (Beanie Feldstein) considers how to move on with her life, and Paula Jones (Annaleigh Ashford) makes desperate choices. Watch preview. 10:00 PM ET on FX

Swap Shop: Complete first season. In rural Tennessee, the “Swap Shop” radio show shares the scoop on sweet deals, igniting fierce competition among collectors of cars, comics, and shoes, all hoping to take advantage of a hot resale market. Watch trailer. Streaming on Netflix

Great Escapes with Morgan Freeman: Series premiere. The Oscar-winning actor serves as executive producer and host of this new series about the world’s most notorious prison breaks. First up: Alcatraz. Watch trailer. 10:00 PM ET on History Channel

The Bachelorette: Just as the dust settles among the guys, Chris S. further stirs the pot when he tells Michelle that "some guys think they have it in the bag." Watch preview. 8:00 PM ET on ABC

The Voice: Two artists from each team are revealed to be safe by America’s vote, while each coach selects one more contestant to move forward. The remaining contestants must compete in the Wildcard Instant Save, but only one will move on to the Top 13 next week. 8:00 PM ET on NBC

Dear Rider: Original documentary. HBO embraces winter with this documentary about Jake Burton Carpenter, a snowboarder who turned his childhood pastime into a cultural phenomenon. Watch trailer. 9:00 PM ET on HBO

NBA Basketball: TNT presents back-to-back games tonight:

• Milwaukee Bucks at Philadelphia 76ers 7:30 PM ET/4:30 PM PT
• Portland Trail Blazers at Los Angeles Clippers 10:00 PM ET/7:00 PM PT

FBI: As pressure mounts from the NYPD, the team must track down a shooter targeting detectives from the same precinct, but Tiffany (Katherine Renee Turner) finds that her NYPD roots may be influencing her view of the situation. Followed by new episodes of FBI: International and FBI: Most Wanted. Watch preview. 8:00 PM ET on CBS

Little People, Big World: Amy and Chris’ Happily Ever After: Special presentation. TLC’s cameras are on hand for Amy Roloff and Chris Marek’s wedding day in this two-hour special. 9:00 PM ET on TLC

Chucky: As Jake (Zackary Arthur) and Devon (Björgvin Arnarson) progress in their relationship, enemies and allies from Chucky's past appear. Watch preview. 10:00 PM ET on SYFY and USA

Claire Spellberg Lustig is the Senior Editor at Primetimer and a scholar of The View. Follow her on Twitter at @c_spellberg.