Gten Ragnarok lit. The Riddle Ragnarok or just simply Ragnarok is a 2013 Norwegian action adventure film about the legendary story of Ragnark.
Sigurds presentation for new project funding falls flat, causing him to miss daughter Ragnhilds endofschool singing recital. At home that night his coworker Allan brings in a stone tablet they interpret as a map of an island in a lake, though they cant translate all of it. He decides to spend the summer vacation doing fieldwork and brings his children Ragnhild and Brage with him. When Sigurd et al. land in Finnmark they meet up with Allans field partner Elisabeth and hired guide Leif and have to hike for days, crossing the old WWII boundary with Russia. They make a raft and get over to the small island Eye of Odin without incident. The party splits up, the children wandering off in boredom and exploration. Ragnhild finds more Russian leftovers and Brage finds a cave. The party all descends into the cave and start finding Viking relics. Brage finds an interesting rock in the shallow water and stows it in his rucksack for later. Leif is unimpressed with Sigurds plan to turn the pieces over to a museum in Oslo and takes them at gunpoint, stranding the rest in the cave. As he is paddling back across the lake in the partys raft he gets taken from below by an unvisaged thing. Elisabeth climbs up the cave wall and reestablishes the ropes so the others can escape the cave too. They sleep in a bunker that Ragnhild found only for the men to redescend the cave to look for more pieces. They discover the cave isnt a hidey hole for treasure but a graveyard for a giant pebbleskinned sea serpent that the Vikings likely used as a format for their dragonprowed ships. This causes them to reassess their earlier opinion, that the stone tablet is not in fact a map but a warning. Meanwhile, Brages rock is shown to be a hatching egg for the same sea serpent family. In fright they capture it in an old metal box and latch it in. The infant serpents squeals transmit down the bunkers cable into the water and alert the adult serpent who hauls the bunker into the lake, trying to get to the baby
Source: Wikipedia