Sea Beast, also known as Troglodyte, is a Canadian-American 2008 Horror/Syfy Channel movie starring Miriam McDonald, Daniel Wisler, Brandon Jay McLaren and Corin Nemec. It was released to DVD on June 30, 2009. It is the 16th film of the Maneater Series.
Will is fishing with his crew in a thunderstorm. As they try to pull the fishing net in, a wave hits the ship and one crew member, Joey, is suddenly spat in the face, attacked, dragged into the sea, and killed by an invisible creature. The mysterious creature attaches itself to the bottom of the boat.
Back at the village, a funeral is held for Joey. Will finds slime on his boat where Joey was taken. Two of Will's crew, Danny and Drew, are secretly planning to go to a nearby island with their girlfriends Carly (Will's daughter) and Erin. Drew, because of work, plans to join the others the next day but is devoured at the dock by the hideous beast that was attached to the boat.
The next day, Will and Arden look for Drew but find his severed arm in the water. They also find slime on the platform of the dock. Back on the island, Carly finds Erin on the beach waiting for Drew. After Carly leaves, Erin sees the boat drifting away. She goes to pull the rope back in but is spat on and paralyzed by the beast and then killed. Will confronts Ben, who lost a crewman the same way Will did, asking him to tell the people what he really saw.
While gathering firewood, Danny is startled when a smaller beast suddenly appears. It bites him on the hand when he tries to take a picture of it. Will meets Arden, who tells him the slime is a toxin. As they discuss the beast they are interrupted by the beast killing two teenagers. Will gives chase but it escapes. Danny and Carly go to retrieve the first aid kit from the boat but find the boat missing. Danny suspects that Erin took it to go confront Drew. Sheriff Jay, Roy and two other men organize a hunting party but are killed by the beast. Arden goes scuba diving to investigate the situation and finds an egg laid by the beast that has already hatched. She concludes that there are more eggs.
Danny and Carly find Erin's corpse and flee back to the cabin. The smaller beasts attack them at the cabin. They manage to kill a few of the beasts on the second floor. A swarm of them appear downstairs, so they lock themselves in the bathroom. Will and Arden find the hunting party slaughtered. Barbara, the harbor master, radios Will and tells him that Ben is setting a trap on the dock, using himself as bait. Danny and Carly make a break for it when the coast is clear, but are ambushed by a lone beast which Danny manages to kill as it attacks Carly. Will and Arden head back to find Barbara's headless body lying on the platform of the dock and Ben killed by the beast's venom. Will discovers that Ben tagged the beast with a GPS tracker and that it is heading for the island.
Carly and Danny fled from the cabin to an abandoned ferry to check if they can radio for help. The beast realizes they are inside and calls for the smaller beasts. Will and Arden go to save them. When they find Danny, who is about to lead them to Carly the beast kills him. Meanwhile, in the kitchen, Carly kills the smaller beasts that tried to attack her. She escapes and rejoins Will and Arden. They find a nest filled with eggs. The mother beast attacks them but Will holds it off while Carly and Arden flee from the ferry. The creature attacks Will, but he survives and blows up the ship, exterminating all the beasts and the eggs. Will, Carly, and Arden decide to start their own fishing business, ending the film.