WARNING: The following contains spoilers for Superman: Man of Tomorrow, available now on digital HD.
Superman: Man of Tomorrow ends on a successful note for the Man of Steel as he foils Lex Luthor and saved Metropolis with the aid of Parasite. The monster absorbs a nuclear reactor meltdown, dying the process, but it helps the public understand Kal-El of Krypton and people he vouches for are here to protect them.
With Lois Lane and the Daily Planet reporters also accepting aliens who helped in the final battle such as J'onn J'onnz and Lobo, Clark Kent grows confident he can defend Earth against threats, domestic and foreign. However, as he embraces his new destiny, a few threads are left hanging.
FINDING THEIR TRIBES
Lobo revealed he lied about Superman and J'onn being the last of their kind when he hunted them down. A follow-up could see Superman changing his mind about staying on Earth, using his ship's relic to go find them, with his cousin, Kara/Supergirl, possible making an appearance.
As for J'onn's search, the sequel could see Kal-El can join him to explore the cosmos or Martian refugees coming to the planet. Seeking haven is a big aspect of this film, with Kal giving a speech on acceptance and equality that speaks a lot to the immigrant issue in so many countries right now. Having Clark as a journalist working (and possibly falling in love) with Lois on this refugee angle would also make some big real-world statements.
LEX'S BIG RETURN
Lex tries to help Superman, but he turns on the Kryptonian and Parasite, wanting to use a Kryptonite ring to kill them. J'onn apprehended him to send him to the slammer for 15 more years, but what happened to the ring remains a mystery. A follow-up can focus on Lex using the ring to create weapons or maybe even super-soldiers to fight Superman.
The government could even use the ring to cultivate these contingency measures in case Superman ever turns on America. They'll surely have trust issues with godlike beings policing the planet, and given that Lex was spying on STAR, he could have stolen their tech and research. He can add to his LexCorp tech to make war-suits and other anti-Superman weaponry, including Kryptonite substitutes.
THE WORLD'S FINEST
Martha Kent joked about Batman's suit in the newspapers, so seeing as the Dark Knight is out there, a sequel could focus on him coming to Metropolis to investigate the destruction by these aliens. The creative team can follow a Batman v Superman route where the Caped Crusader wanted to leave Gotham to understand more about this weapon of mass destruction, but rather than fight him, they could work together.
This could serve as a possible start to the Justice League, with Martian Manhunter another candidate to join. It would also be a great opportunity to paint a Batman that's not so violent and cynical, something Warner Bros. has prided itself on lately. A well-oiled Batman and Superman relationship could find them taking on enemies like Darkseid or Joker, something that would blow this franchise wide open.
Directed by Chris Palmer, Superman: Man of Tomorrow stars Darren Criss as Clark Kent/Superman, Zachary Quinto as Lex Luthor, Alexandra Daddario as Lois Lane, Ryan Hurst as Lobo, Brett Dalton as Rudy Jones/Parasite, Ike Aamadi as Martian Manhunter, Neil Flynn as Jonathan Kent and Bellamy Young as Martha Kent. The film is available now on digital HD and on Blu-ray and 4K UHD on Sept. 8.