Justice League Action - Season 1 - Eps 18: Field Trip
As Superman gives Blue Beetle, Firestorm, and Stargirl a tour of the Fortress of Solitude, they run afoul with General Zod, Faora, and an unidentified Kryptonian villain who are accidentally freed from the Phantom Zone. Now with Superman trapped inside, the three teen heroes must work together to stop the Kryptonian villains.
About Justice League Action

Title: Justice League Action
First Air Date: 2016-12-16
Last Air Date: 2018-02-10
Status: Ended
Rating: 7/10 (from 84 votes)
Language: EN
Seasons: 2
Total Episodes: 52
Network: Cartoon Network
Genres: Animation, Action & Adventure, Sci-Fi & Fantasy, Kids
Production Companies: DC Entertainment, Warner Bros. Animation
Synopsis
Batman, Superman and Wonder Woman lead the DC Super Heroes against their most infamous foes.