Report: Stas is a prequel to the second part of the Report series. It will tell you a story, about a former Black Mesa security guard by the name of Stas. Events take place 2 hours before Gerald's arrival.
Stas's story, the former guard of Black Mesa and Gerald's friend, will tell you about the beginning of the uprising, although not as large-scale as you think. And will also show the events that happened after Gerald went to carry out the task in Report II.