How did life on Earth begin? What does the search for life in the distant past tell us about the search for life on distant planets? How should the most ancient and ambiguous putative biosignatures be critically evaluated? How did the Earth–life system evolve through the dramatic upheavals of the Precambrian–Cambrian boundary? When and why did eukaryotes begin to produce mineralized skeletons? These are among the astrobiological questions to which palaeobiologist Martin Brasier made profound contributions in a career spanning nearly half a century and tragically cut short late last year. Here, we summarize and celebrate Martin's contributions to astrobiology.