While delivering a letter to a house that never gets mail, the gang goes through warfare to get to its front door. Parker's anxiety escalates when the cloud appears to be the source of loud nightly thundering plaguing the town.

When Angus accidentally throws Burt away, he and Parker must get him back from Greenwood's Recycle King. After Angus tells Parker and Russell to leave the house on his day off, Parker wrongly assumes it's permanent.

Angus agrees to compete against Mayor Peeve's new POSTBOT in a "mail-off" to save the Middlemost Post. Parker's anxiety escalates when the cloud appears to be the source of loud nightly thundering plaguing the town.

After one of Lily's inventions goes haywire, she enlists Parker's help to get it back under control. Angus loses his lucky beanie, which causes him to revert back to being a child.

Parker accidentally loses one of Russell's teeth and hurries to find a replacement before Angus finds out. On Free Toast Day at the Middlemost Toast, Parker does whatever it takes to make sure Angus enjoys the holiday.

Parker's new friend turns out to be a Leprechaun in pursuit of the gold at the end of Parker's rainbow. When Parker finds mysterious love letters written by Angus, the little nimbus goes all over town to find who they're meant for.