This clip from DC's Legends of Tomorrow is a bit spoilery in that it flat-out tells you the guest villain. Now, it's a villain that has been talked about during the San Diego Comic-Con panel and has shown up in previews, so most people already know that he's coming. But just in case, I'll talk about it more after the image below…
From the looks of the scene, the Legends have gone back into 1968 Vietnam to find an anachronism. Though this is the height of the war, the team finds an area where U.S. soldiers are working with the Viet Cong. Ray (Brandon Routh), Amaya (Maisie Richardson-Sellers), and Zari (Tala Ashe) are posing as journalists being taken to the leader of this area. Ray talks about having a bad feeling, and he definitely should, as they are taken to see Gorilla Grodd.
This seems to be the week to kick things into high gear, as Supergirl introduced some of the Legion of Super-Heroes, The Flash is going up against the Thinker, and Arrow is going up against Cayden James — all right before the big Arrowverse crossover event, Crisis on Earth-X.
DC's Legends of Tomorrow airs tonight at 9 p.m. ET on the CW.