Episode #105 "Post-Nasal Dick"

When Tommy comes down with a terrible cold after a make-out session with his lab partner, Dina, the other aliens also get sick for the first time, and they're all convinced that they're dying. Although he feels dreadful, Dick accompanies Dr. Albright to a wedding where his eccentric behavior soon makes them the center of attention. When Dick drags Dr. Albright onto the dance floor for a spirited tango, she discovers that he is extremely ill and insists that he go home with her. Fearful that he may die during the night, Dick confesses that he's an alien and that he loves Dr. Albright. After he recovers, Dick fears that he may have revealed his secret during his delirious ramblings but finds that all Dr. Albright remembers is his profession of love.