When they were rookies

With the release Friday of "The Avengers: Age of Ultron," it's the perfect night to take a superhero refresher course. The stakes don't seem particularly high in 2012's "The Avengers," but director Joss Whedon does a nice job of giving every character a chance to shine. 6 p.m. FX

Hosts with the most

The morning-show wars intensify when "Today's" Hoda Kotb takes on "Live With Kelly and Michael's" Michael Strahan for "Lip Sync Battle." So who gets to perform "Good Day, Sunshine"? 9 p.m. Spike

Roughing it

At first glance, I thought "Naked and Afraid" was a documentary about how I get up every morning. Fortunately for you viewers, it's about tough folks battling the elements. In this "pop-up" edition, an Army mom and a U.S. Marine take on the Florida Everglades. 9 p.m. Discovery

Neal Justin