Tuesday’s TV highlights

SERIES

Pretty Little Liars: Now that they’ve let Dr. Sullivan (Annabeth Gish) in on the secret of “A,” Aria, Emily, Hanna and Spencer (Lucy Hale, Shay Mitchell, Ashley Benson, Troian Bellisario) must pay in the season finale (8 and 10 p.m. ABC Family).

Auction Kings: This new episode features a flag-themed guitar signed by Bruce Springsteen and a Cadillac that was once owned by Elvis Presley (9 p.m. Discovery).

Combat Hospital: “Triage”: Rebecca takes control of triage when an explosion injures Col. Marks in this new episode (10 p.m. ABC).

POV: Danish filmmaker Janus Metz’s documentary “Armadillo,” follows soldiers from Denmark as they embark on their first mission in Afghanistan (10 p.m. KOCE).

Chopped Champions: In this new episode four past winners return to compete against one another (10 p.m. Food).

Quirky: The premiere of this invented gadget series features an all-in-one pasta strainer and a revolutionary power strip (10 p.m. Sundance).

Web Therapy: After being knocked for a loop by the discovery of Kip’s (Victor Garber) secret life, Fiona (Lisa Kudrow) resolves to expose the impostor in the family in this new episode (11 p.m. Showtime).

SPECIALS

9/11: Where Were You?: The life and death decisions people made during the chaos of the 9/11 attacks help illustrate the day that is etched in memory for so many (7 and 10 p.m. National Geographic).

SPORTS

2011 U.S. Open Tennis: First round (10 a.m. and 4 p.m. ESPN2).

Baseball: Regional coverage (4 p.m. MLB); the San Diego Padres visit the Dodgers (7 p.m. KCAL); the Angels visit the Seattle Mariners (7 p.m. FSN); the Chicago Cubs visit the San Francisco Giants (7 p.m. WGN A).

WNBA Basketball: The Seattle Storm visit the Sparks (7:30 p.m. FS Prime).