Inspired by The Thing, this adventure sends your party to sea aboard the Osmorton. Mid-way through the trip, the crew rescues a man lost at sea - a man infected by a neural parasite that causes the host to fall under its control. Infected passengers are nearly indistinguishable from their former selves, but want nothing more than to continue to spread the parasite to others. This adventure comes with a unique betrayal encounter that presents an extra level of fun to this one-shot. It is intended for more advanced groups that can dive deeply into their roleplaying and who are willing to approach problems in non-linear ways. Can your players find out who is infected and who is safe before the ship reaches its destination or will Captain Drustan need to scuttle the ship to ensure the survival of humanity?