Howard (voice by Chip Zien) is a humanoid duck living on "Duckworld", an alien planet which resembles Earth in several ways. One night he is teleported in Cleveland by a laser beam during an experiment performed by the Cleveland physicist Dr. Walter Jenning (Jeffrey Jones). While still confused by the cosmic travel, Howard saves Beverly Switzler (Lea Thompson) from the attentions of a band of thugs. Beverly invites Howard round her flat and the morning after she takes him to see Phil Blumburtt (Tim Robbins), which unfortunately is a janitor and not a scientist as she believes. Howard, always cynical and sarcastic, decides to play alone but his first attempts to have a normal life on Earth are not very successful. In due time Howard will meet the scientist who, unwillingly, is the culprit of his planetary relocation (and who may be able to send him back) and he will take the Earth destiny in his wings, facing a possible invasion by other less sarcastic but more nasty aliens.