Geologist Kathleen Dawson is in the South American jungle in search of oil, but her guides are terrified of the Jaguar Man. Kathleen doesn't believe in the mythical shape-shifter who, according to legend, rules the jungle both as beast and man, protecting his territory against the outside world.

Then Kathleen is drugged and awakens to find herself in a cave with a man named Guerriro who claims to be responsible for the Jaguar Man myth. He warns her to leave before it's too late. When morning arrives, Kathleen's back in camp and convinces herself the man and the cave were only a dream. However, her guides find a jaguar's skull on a pole, which is the Jaguar Man's warning that to stay means death. The frightened natives abandon Kathleen.

Stranded in a rainstorm that quickly escalates into a flood, Kathleen fights for her life. She's saved by a black jaguar and again finds herself in Guerriro's cave. But as the days pass, Kathleen begins to wonder if Guerriro, who is both her captor and her savior, really cursed to live his life as a black jaguar by day and a man by night.

All Kathleen knows for sure is that Guerriro's ensnared her heart, and she'll do anything she can to stay by his side, even if doing so means she must...Hold Onto the Night.