Hosted by the award-winning non-binary comedian Mae Martin, Fluid explores the science of gender and sexual fluidity in the natural world. The film debunks pseudo-scientific myths and introduces cutting-edge research to reveal that in a very real sense, we are all gender fluid.

Guided by eminent biologists Joan Roughgarden and Justin Rhodes, alongside famed primatologist Frans de Waal, Mae discovers a hermaphroditic ginger plant, sex-changing fish, and mammals – including lions, hyenas and chimpanzees – which display surprisingly non-normative sexual traits. Meanwhile, in the human realm, Mae meets with trans historian Jules Gill-Peterson to explore the misguided gender studies of the 1970s and 80s, while seeking out the latest information from researchers including Princeton-based child psychologist Kristina Olson and prominent neuroscientists Gillian Einstein and Lise Eliot. The doc also meets with three young trans scientists who are revolutionising  the field by centring a fluid perspective on gender in their research.

Along the way, Mae shares their own observations and reflections in hilarious material from their globally-renowned standup shows.