Ensam är pest

After discovering his sexpot girlfriend in bed with another man, writer Larry (Steve Martin) begins to feel that he is becoming something of a "'lonely guy"'. His feeling of isolation is reinforced after an encounter with fellow sad loner Warren (Charles Grodin), who advises him to buy a fern for company and give up all hope of ever finding another life partner. However, after penning a manual based on his experiences Larry once again finds romance... but for how long?