"Plague of Madness" is the seventh episode of the first season of the American animated action-drama series Primal.
It premiered unannounced on Adult Swim on April 1, 2020, as part of Adult Swim's annual April Fools' Day stunt, as a joking reference to the COVID-19 pandemic, after "Rage of the Ape Men", before formerly airing in its chronological place in the series (between "Scent of Prey" and "Coven of the Damned") on October 11, 2020.
Horrified, the two immediately flee through the jungle into a ravine, where the Argentinosaurus knocks itself out, and Spear and Fang rest in a cave.
On being burned by a lava geyser, the Argentinosaurus jumps towards them, breaking through the crust into the lava below, and allowing Spear and Fang to ride a wave to safer ground and resume running, as the Argentinosaurus repeatedly re-emerges and sinks, unable to climb out but still pursuing them.
As the Argentinosaurus is slowly incinerated to ash, Spear and Fang observe its final agonizing moments in shared grief and dismay.