Tom Smallwood was fishing when caught in a storm. He was washed overboard and tangled in his own nets. While submerged, he located a Plodex egg and grasped for it. He realized it was alive. When he untangled himself from the nets, Tom took the egg with him. Back home, his wife Gladys broke open the egg to discover an alien baby girl, Marrina. The aging couple were already raising their grandson, Dan Smallwoom. They decided to raise the girl as well.
The Smallwoods raised her well and the small fishing community accepted her despite her strange appearance. But teenaged Marrina discovered her appearance came with amphibious powers. She was soon recruited to Department H. Marrina would never return to her adoptive family.