Mary has been working the high ports in the New Greenland system for some time. Because of her efficiency, she's been transferred to Reef Island to manage the port there, since she is effective, and the port ships out large quantities of liquid hydrogen as energy stores for other cities, and needs good management and security.
She is readying large shipment S7 to go out in the next thirty minutes, and is talking to one of her shift supervisors when she sees a group of medical personnel rushing away from container rack A in the warehouse. She stops them by the elevator, and they tell her they took a woman named Phoenix at the behest of an armored woman with BSI colors to a container on row A level 3.
She goes to investigate, but just as she's reaching row A she sees the automated gantry systems lift a container from that row and place it in row C, and return another container to the A3 location. So she goes instead to row C. She sees someone has added a scheduled move to her calendar without her authorization, and she can't access the move order: Access Denied / Security Override. The container is supposed to go out on S7, rush-rush. So she climbs up and opens the container (a fully pressurized, heated one), and inside recognizes Phoenix lying unconscious on her gurney, and Eden standing over her. But she just barely sees Tennan unlimbering her weapon and then Fos bringing his huge hammer-like fist down on her head, and that's the last thing she remembers.