理查德·阿米蒂奇

Richard Armitage

饰：Self - Narrator,

Natasha Pring

饰：Emily

Erik Twight

饰：Lead Sperm

Jaqueline Wingfield

饰：Lead Sperm

Kai Almeida-Jones

饰：Baby

Chris De Jonge

饰：Himself - Fertility Expert: University of Minnesota

Joanna Ellington

饰：Herself - Sperm Physiologist

Andy Malone

饰：Sperm

Geoffrey Miller

饰：Himself - Evolutionary Psysiologist: University of New Mexico

Alex Travis

饰：Himself - Reproductive Biologist: Cornell University

Zita West

饰：Herself - Fertility Expert

理查德·阿米蒂奇

Richard Armitage

饰：自己

Allan Pacey

Allan Pacey

饰：Self - Sperm Expert: University of Sheffield,(as Dr Allan Pacey)