Curucu, Beast Of The Amazon 1956

Curucu, Beast of the Amazon is a 1956 American adventure/monster film, directed and written by Curt Siodmak and starring John Bromfield, Beverly Garland and Tom Payne. The title creature is pronounced "Koo-Ruh-SOO" (Portuguese: Curuçu). The film was distributed in the United States as a double feature with The Mole People.
Plantation owner Rock Dean (Bromfield) travels up the Amazon River to investigate why the workers have left in panic. Dean's guide, Tupanico (Payne) warns him of Curucu, a birdlike monster who is said to live up the river where no white man has ever been. Accompanying him is Dr. Andrea Romar (Garland), in search of a drug which (in this story) the natives use to shrink heads. She hopes this drug will be effective in reducing cancerous tissue.
Tupanico guides the couple through the jungle, where they see a strange shimmering form in the river which drives the bearers away. After Rock shoots an animal, Tupanico offers to clean his rifle for him. Rock reluctantly agrees.
Later, Curucu attacks. Rock shoots at it, with no effect. The monster is revealed to be Tupanico, who is trying to drive "his" people away from the plantations, where he can lead them in the old ways, before white men brought civilization and disease. Tupanico used the excuse of cleaning Rock's rifle to load it with blanks.
Before they can be killed, Rock and Andrea are rescued by natives friendly to the local missionary. After wandering lost in the jungle in the commotion, Andrea wakens to find herself and Rock at the mission. A grateful native, whom she treated earlier, gives her some gifts: the shrinking drug she was searching for, and the shrunken head of Tupanico.