When their day-old pet goldfish dies after the kids overexert him, they're given the responsibility of flushing him down the toilet. Dee Dee balks at the task, and puts the fish on top of the toilet -- out of Dexter's reach -- until he can be given a decent burial in the garden the following day. When the ghost of the goldfish haunts them, An earthquake releases a strain of mutant cockroaches with the ability to start fires, which proceed to cause destructive chaos in a small town. The studies carried out by Chick and 5629, however, reveal an intent with much more far-reaching consequences. Dexter & Dee Dee decides it's time to get their ghost-busting gear.