Deep inside the Palombian jungle lies Monte Urticando, an ancient, nigh inaccessible volcano where millennia old cactuses grow. Every 15 years they flower, and the pollen temporarily drives away most of the dangerous predators. For the Marsupilamis, though, it's also the signal for a strange and cruel tradition: it's time for the young Marsus to learn how to fend for themselves, away from the protection of their parents. Will they learn to work together to survive?

Gold has been found in the Klondike, a remote region in the Canadian far north! Jasper, the manservant of `Tenderfoot' Waldo, went to try his luck ... and vanished. Worried about his man, Waldo calls upon his old friend Lucky Luke. The two men will have to make the dangerous trip to the Klondike, only to face all those who, in that desolate, inhospitable land, will stop at nothing in order to fleece their fellow man.