Creature From the Black Lagoon
The following description comes from the event organizer.
When the missing link is discovered to be swimming in the Amazon river, scientists set forth to capture it for study. But the creature would much rather stay in its home away from nosy humans. That is, until it sees the head scientist's girlfriend and realizes it may be both a lover and a fighter. One of the classic Universal Monster flicks hits our screen in case anyone wants to see a different film about creatures under the water...