HBO‘s Lanterns is taking some of the most iconic Green Lantern characters and bringing them to vivid life like never before. Case in point? Lanterns Episode 2 ends with the eerie arrival of one of the DC Comics’ greatest villains: Sinestro.

**Spoilers for Lanterns Episode 2, now streaming on HBO Max**

Lanterns Episode 2 largely picks up where last week’s premiere “Pilot” left off. In 2016, Hal Jordan (Kyle Chandler) and John Stewart (Aaron Pierre) are trying to figure out what a handful of aliens disguised as humans were doing in Rushville, Nebraska and why they were gunned down at a high school football game.

When Hal dispatches John to Coast City to retrieve his lantern (to recharge his ring), the younger trainee is captured by a group of aliens who explain that a Manhunter is hiding in Rushville. It’s John’s duty to discover who the Manhunter is, or else they will blow up the entire town in due course, killing hundreds, if not thousands, of innocent humans.

Even though John is sworn to secrecy, he tells Hal about the Manhunter. It’s immediately obvious that Hal is taken aback by the very idea that a Manhunter could not only still be alive, but operating in Rushville. At the end of Lanterns Episode 2, Hal changes into his official Green Lantern suit and soars into the sky. We next see him arrive at an intergalactic prison where he visits the red-skinned alien, Sinestro (Ulrich Thomsen).

Who is Sinestro in the comics? Who plays Sinestro in Lanterns? Why is it such a big deal that Hal is visiting this guy? Here’s everything you need to know about Sinestro in Lanterns Episode 2…

Lanterns Episode 2 Ending Explained: Who is Sinestro?

Thaal Sinestro is a former Green Lantern from the planet Korugar in space sector 1417. Created by John Broome and Gil Kane, Sinestro first appeared in Green Lantern (vol. 2) #7 all the way back in 1961.

Sinestro’s backstory is fascinating because, similar to Hal Jordan, his connection with the Green Lantern Corps begins with a Green Lantern crash landing on his home world. Sinestro discovers the injured Lantern Prohl Gosgotha near an anthropological site he was studying and borrows his ring to fight off Gosgotha’s attacker, a Qwardian. Sinestro winds up using the ring to crush the Qwardian with the ruins he was hitherto trying to restore. When Sinestro returns to the crash, Gosgotha is still alive and asks for his ring back. Sinestro refuses, letting the Green Lantern die and tricking the Guardians into believing he is the ring’s new chosen one.

Sinestro quickly becomes an incredibly successful and well-respected Green Lantern, known for maintaining peace in his sector by any means necessary. He eventually uses the power of the ring to become an autocratic dictator ruling over all of Korugar. A young Hal Jordan is assigned to be Sinestro’s trainee. The two become close, but the more Hal learns about Sinestro’s brutal methods, the more concerned the human grows. Hal eventually reports Sinestro to the Guardians who imprison him.

That’s why we find Sinestro in prison on the Guardians’ homeworld of Oa at the end of Lanterns Episode 2.

Who Plays Sinestro in Lanterns? Meet Ulrich Thomsen

Danish actor Ulrich Thomsen plays Thaal Sinestro in Lanterns. The 62-year-old actor is perhaps best known for his work in 1998’s The Celebration, but you might recognize him from the show Banshee.

“Ulrich, what a jerk, that guy! Let me tell you!” Kyle Chandler said sarcastically when DECIDER asked him about Thomsen. “Wonderful, fantastic. I think the first day I met him, he was already in costume, in the red.”

“I never saw him out of [the red makeup],” Aaron Pierre said.

“You didn’t?” Chandler asked.

“No,” Pierre confirmed.

“Handsome man. Handsome fella! Really nice guy, really nice guy,” Chandler said. “We had a lot of fun working and the scenes were interesting because we discussed our relationships and got into a little bit of it. And then we just jumped into it.”

“Yeah, a real pleasure, an honor to work with them and like everyone else that they cast on the show, in my opinion, stellar.”

Lanterns Episode 3 will be on HBO and HBO Max on Sunday, August 30.