Hal Jordan’s greatest nemesis is joining him on the small screen. HBO’s Lanterns TV series has cast Ulrich Thomsen as the villain Sinestro in the Green Lantern show.

Sinestro is a former Green Lantern who was discharged for abusing power, and he became the leader of the Sinestro Corps, the Yellow Lanterns powered by fear. He was created by John Broome and Gil Kane, who introduced him in 1961 and has been behind several of Green Lantern’s most difficult conflicts.

Thomsen is known for many Danish productions like Festen, as well as The World is Not Enough, and American shows Banshee, The Blacklist, and The New Pope.  

He joins Kyle Chandler and Aaron Pierre as the Green Lanterns Hal Jordan and John Stewart, respectively. The cast also includes Kelly Macdonald as the no-nonsense Sheriff Kerry, Garret Dillahunt as ruthlessly ambitious cowboy William Macon, and Poorna Jagannathan as Zoe, the confident and poised potential love interest for John Stewart.

Lanterns takes place when new Green Lantern recruit John and veteran Green Lantern Hal work together to investigate a murder. The show is part of James Gunn and Peter Safran’s new connected DCU, and the mystery in Lanterns will continue into the first phase of their connected movies and TV shows, titled Gods and Monsters.

The eight-episode series is co-written by Chris Mundy, Damon Lindelof, and Tom King. James Hawes is set to direct the first two episodes. The show is expected to debut in the summer of 2026.