Judging that alternate Earth-238 was retrograde and that its lack of progress might have a knock on effect to other Earths in other realities if the problem was not solved, the Dimensional Development Council sent Omniversal Majestrix Saturnyne and her Avant Guard to 238 to administer an evolutionary push via a mutagenic liquid. However, during preliminary preparations on 238, some of the liquid leaked out into the surrounding environment, and a rat in the sewers near the Avant Guard's covert subterannean base was evolved into a sentient humanoid, who dubbed himself Algernon and set up a modest home, trying to emulate his impression of a human gentleman. Though she soon discovered her new neighbor, Saturnyne initially decided to simply keep him under observation, judging him no threat to the mission. However, six months later, with the Push imminent, Captain Britain of Earth-616 was sent to 238 by Merlyn; after fighting a mechanical entity, the Junkheap that Walked like a Man, similarly created by the leaking evolutionary liquid, Captain Britain followed the flow back to Algernon. The rat treated the surprised hero as a welcome house guest, but Saturnyne, alerted to Captain Britain's arrival and fearful Algernon might reveal too much, sent the Avant Guard to stop the hero. During the ensuing fight, Algernon was accidentally hit by one of the Guards' devolvo-rays, regressing him to being a normal rat.