When a disco boat hosting a fancy dress party comes under attack from a killer shark, Cutter and the team realize they have a new underwater incursion. But a grisly discovery during the post-mortem suggests the creature may not have come from the past. The creature's secret weapon is a ferocious, giant proboscis that shoots from its jaws to trap its prey. Cutter has never seen anything like it and is convinced they are dealing with a species from the future.
On the other side of the city, a group of teenagers is playing basketball near a flooded drain. When one of the boys wanders too close, something snatches and drags him below ground. Cutter arrives and discovers the flooded drain leads directly to the canal where the disco boat was moored. It looks like a second shark may be at large and has swum up the drain.
Cutter and the team pursue the creature back towards the canal only for it to disappear without trace. With no sign of any anomaly, Cutter is at a loss to explain where the creature has gone. Cutter starts to wonder if they could be looking for a second, entirely different creature.