In a metropolis of the eastern hemisphere, inhabitants are gripped by fear and law enforcement perplexed, as the entire urban landscape becomes inundated with an enigmatic phenomenon: mustaches painted ubiquitously on advertisements and even unsuspecting individuals. Amidst this puzzling scenario, Daffy Duck emerges as the self-professed culprit, breaking the fourth wall to the audience and justifying his actions through poetic verse. With whimsical resolve, Daffy reveals his singular mission: to adorn every countenance with a mustache.
Porky Pig assumes the role of a police officer, devising a stratagem involving a picture frame to ensnare Daffy. However, Daffy outwits Porky with a cunning ruse, transforming himself into a Christmas present to perpetrate his mischievous deed. Engaging in a pursuit through the city's subway system, Daffy deftly eludes Porky while adorning commuters with mustaches, further complicating the pursuit.
As the chase escalates, Porky confronts Daffy atop a towering billboard, culminating in a precarious confrontation where Daffy seemingly plunges to his demise, only to orchestrate yet another mischief by adorning Porky with a mustache. The chase ensues with escalating absurdity, involving a motorbike pursuit, a crash through a skylight, and Daffy's strategic placement of additional mustaches on Porky.
Ultimately, the escapade culminates in a courtroom scene, where Daffy stands trial before a stern bulldog judge and a jury adorned with mustaches. Following a verdict of not guilty, Daffy vows to forsake his mustache-drawing endeavors, opting for beards instead. However, true to his irrepressible nature, Daffy concludes his antics by defiantly adorning the judge with a beard and obscuring the screen with paint.