Helena Walker, an Australian paleontologist from 21st-century Earth, becomes a grieving widow after the death of her wife, Victoria. One night, drowning her sorrows in pills and wine, she awakens to find herself adrift in a vast ocean. After narrowly escaping a charging megalodon, she washes ashore on a mysterious island. There, she befriends a wild Dodo, only to discover it is being hunted by a tribal hunter named Bob. Learning they both arrived in this world under similar circumstances, Bob teaches Helena the ways of survival. In this strange new world teeming with dinosaurs, enigmatic technology, and warring tribes, Helena must do whatever it takes to survive and hopefully find a way back home, gaining new allies and making formidable enemies along the way.