Professor Steinachs Metode el. Foryngelseskuren / The Rejuvenation Treatment (1920) dir. Robert Storm Petersen

A scientist has invented a serum that transforms the old into young and the old into new. His first subject – a very old man – gets a single injection and gradually turns into a baby. Meanwhile, three little men have stolen the syringe with the rejuvenation treatment, which they now give to men and livestock in dire need of it.