Staines Down Drains

Stanley and Mary-Jane view their new home and soon find a sink in their basement which leads to civilization, called Drainland. They soon discover mutant monsters, some of which are friendly.

Stanley starts his first day at school along as Mary-Jane is pretending sick at home, she soon decides to travel down the portal to Drainland again, however she soon finds herself being chased for stealing a Cleansing Sea plant, meanwhile Stanley travels down again to rescue his sister from a large amount of acid which was tipped down the sink.

Betty has taken the job of a comedian, though her jokes are anything but funny. Meanwhile Dr. Drain hears about an Olympic-like event going on and has the Goblers steal the trophy, but Stanley and Mary-Jane notice and pursue the terrible-trio. Stanley, upon donning a Dr. Drain costume gets mistaken for the villain by the Goblers, until they see the real one right beside Stanley. The Goblers couldn't tell them apart (not even by size) until Dr. Drain revealed himself by threatening his lackeys, and he and Stanley officially meet face-to-face. Luckily Stanley gets the trophy back and saves his mom from sheer embarrassment.

Stanley tries to find his sister after overhearing a plan to cover her in chocolate and feathers by the Lupin Lunes, searching in Drainland, he finds Dr. Drain with a growing potion, however eager to find Mary-Jane, Stanley leaves though he can not go out the drain portal after his mother blocks it.

The duo accidentally drop one of Betty's wedding-rings down the drains, so they have to go find and retrieve it as soon as possible. Meanwhile Dr. Drain again tries to destroy the purifying-plants so he can rule the sewers with an iron fist, and believes Betty's ring is the key to do it.

Stanley and Mary-Jane's teacher has the school clean up a toxic waste dump, but Dr. Drain then steals the waste to use it in another takeover attempt. Their skirmishing however has caused the train carrying the waste to go out of control, and worse, Gretel and the Lupe brothers are caught in it too.