The relationship between Grampa and Tom deteriorates after Grampa’s senility and abrasiveness embarrasses Tom at the elementary school. At around the same time, one of Grampa’s fellow-veterans of WWII dies, leaving Mr. Bleu as the only other living member of Grampa’s war squad, the Flying Hellfish. In the final days of the war, the unit had removed Germans from a castle when Mr. Bleu discovered several paintings. The group had agreed to place the paintings in a crate, and each member received a key. When all but one of the members died, the final member would inherit the paintings. This type of inheritance is called a tontine. As Mr. Bleu wants the paintings as soon as possible, he orders Grampa’s assassination. To escape death, Grampa moves in with Effe and Lupita, and lives in Tom’s room, putting a further strain on the relationship. This changes when Mr. Bleu bursts in to take the last key to the paintings’ safe. Tom manages to not only keep Grampa’s key but also to steal Mr. Bleu’s, and the two go in search of the paintings. As it turns out, the safe is buried in the lake, so they borrow the neighbor’s boat and retrieve it. Mr. Bleu again shows up to steal it, and throws Tom into the lake. Grampa rescues Tom and gives chase to Bleu, and after the boat hits land, Grampa, who had been Mr. Bleu’s superior in the war, gives his rival a dishonorable discharge for trying to kill his commanding officer. Grampa then announces the paintings are his by default. The victory is hollow, however, as a German shows up to claim the paintings, backed by the US State Department, which had been trying to find the paintings for 50 years. The “rightful owner” is a young German late for a Kraftwerk concert in Stuttgart. Grampa walks away with nothing, except new respect from Tom. No, wait: that was an episode of The Simpsons. Nevermind.