Invincible Season 4 Episode 4 Features Original Underworld Journey

In the latest installment of Prime Video's animated series Invincible, season 4 episode 4, titled "Hurm," protagonist Mark Grayson, known as Invincible, embarks on an unprecedented journey to the underworld, marking the show's first wholly original storyline diverging from the source comic books. Aired on March 25, 2026, the episode pulls Mark into a demonic conflict, expanding the series' lore while deepening his personal struggles.

The episode opens with Mark, voiced by Steven Yeun, grappling with guilt over a recent killing, visiting costume designer Art to reclaim his classic yellow-and-blue suit after briefly adopting a darker one. As he prepares to respond to a call about protecting a young hero from an ancient threat, Damien Darkblood, the demon detective voiced by Clancy Brown, summons him to Hell using a ritual involving Omni-Man's blood. Darkblood, previously banished by Global Defense Agency head Cecil Stedman after nearly uncovering Omni-Man's murder of the Guardians of the Globe, seeks Mark's aid amid a rebellion in the underworld.

Hell, depicted as a subterranean realm deep within Earth rather than a separate dimension, serves as a prison for ancient evils....