This documentary is about microorganisms that live, compete, feed, and breed on the surface or in the depths of our bodies.

Marta Dusseldorp
as Narrator (voice)

Garin Aglietti
as Himself

Kati Angelidis
as Herself

Thomas Borody
as Himself

Maya Coleman
as Daughter

Alan Cooper
as Himself

John Croese
as Himself

Rob Dunn
as Himself

Richard Faulks
as Himself

Andrew Ferguson
as Himself