In this film, he finds Lieutenant Frank Dribin returning to a parody of the procedural police in that period of his life. Lt. Derbin discovers that the new lover of his ex-girlfriend is primarily a guilty person. This friend involved appears to be a key partner in a plot to kidnap a scientist who advocates solar energy.
What's at work here is the comedy law of diminishing returns: if you tell the same jokes over and over and over again, they become less and less and less funny.
Nielsen combines B-movie earnestness, exuberant mugging, and a trouper's slightly desperate cheerfulness: he turns this rather alarming character into a sweet, ebullient lunatic -- albeit one who's hell on innocent bystanders.