The events and narratives which follow are mostly fictional. Those parts in bold are historical fiction while those in italics are mostly speculation. Sections which lack any embellishment are my explanations and descriptions.
We shall start from a few billion years after the beginning of time, so not the very beginning, but before anything we would call living (at least on this normal little planet orbiting a normal little start in a relatively quite part of a normal galaxy in a mostly empty portion of the universe). We begin when the planet has cooled enough to sustain standing water on the surface. When was this? Some time between 4.4 and 4.2 billion years ago. Approximately two hundred million years after the collapse of the nebula which formed the Sun. The oldest known fossils date to approximately 3.5 billion years ago. This is where our fictional narrative ends, and it shall be denoted as T=0, for dating purposes, we’ll pretend it is PRECISELY 3.5 billion years ago. This is not to say there is no evidence of biological activity before this time, since the oldest evidence for biological activity (in the form of biochemical markers of biological activity) date to 3.85 billion years ago.