Kai Alexander

In 2017, he joined the cast of the award winning Channel 4 comedy Catastrophe in the recurring role of Jeffrey, the on-screen child of characters portrayed by Ashley Jensen and Mark Bonnar.^[5][6] He also played the lead in the BBC Original Drama Short, Oakwood.

In 2019, he reprised his role in the fourth and final season of Catastrophe.^[7][8] He later joined the cast of The Stranger, a Netflix adaptation of the novel by Harlan Coben.^[9][10]

He portrayed Richard Branson in the 2022, Danny Boyle miniseries, Pistol created by Craig Pearce for FX, following the rise of the Sex Pistols.^[11] Alongside Karen Gillan, as brother and sister, he voiced one of the main characters in the unreleased Disney and 20th Television Animation, Rhona Who Lives by the River.

Alexander portrayed Sgt. William Quinn in the 2024 Apple TV+ miniseries, Masters of the Air, produced by Steven Spielberg, Tom Hanks and Gary Goetzman.^{[1][11][12][13]} Esquire described Alexander's performance as his ‘big break’.^[14] The role involved extensive stunt work, and he performed all of the stunts himself, including a parachute jump.^[15]

In 2025, he played Lyle Jennings in Scott Frank's English adaptation of Jussi Adler-Olsen's Dept. Q. He received rave reviews for his contribution, with his portrayal being described as ‘spellbinding’.^[16] Later in the year, he joined the cast of Angels in the Asylum, the yet to be completed feature starring Simon Pegg and Wind of Change, a biopic of the German rock band Scorpions.

He will next be seen alongside Angelina Jolie and Jason Segel in Anxious People, a feature adaptation of the 2019 novel by Fredrik Backman directed by Marc Forster. Alexander has now collaborated with two of the last three directors from the James Bond franchise as casting begins for the next instalment, with producers reportedly seeking a “fresh face” to take on the 007 mantle.^[17]