Perch fishing with ground and dip has always had a special place in Bård's heart, so he becomes terribly envious when Lars sets a new unofficial Norwegian record for sea bass one October day in the Oslo Fjord. He orders a spur-of-the-moment trip to Egypt with the aim of catching a huge Nile perch and thereby knocking Lars in the boots. After a short toll trip on the Nile, and the worst bargaining attempt in history, the boys take a train to the world's largest artificial lake, Lake Nasser, where the really big Nile perch live.