Hoshi sleeps on the gymnasium floor, but wakes up when Trip and T'Pol walk in. "Thank God you're here -- I've been stuck in here for hours. The door control --" Hoshi says, jumping to her feet. Trip tells T'Pol that "she was here last night -- right over there." T'Pol comms Quantum to find out that there has been no sign of Hoshi on the entire ship. Obviously, the whole point of this scene is to tell us that Hoshi's finally become completely invisible. Quantum comms T'Pol to meet him in Sick Bay, and tells them they will not break orbit while Hoshi is still missing. Trip and T'Pol leave. Hoshi runs after them and makes it through the door before it closes. Although I really don't know why she rushed -- if her hand was able to pass right through those weights, I'm sure she could walk through the door while it's closed.
Sick Bay. Quantum and T'Pol cross-examine Phlox and find out that Hoshi made several visits to him, complaining of feeling left-out and ignored. Phlox shows them the scans he took of Hoshi, which seemed "perfectly normal at the time," but now show that all her molecules are doing a disappearing act. Phlox only took a closer look at them when he heard that Hoshi was AWOL. In the background, we can see Hoshi sitting on a counter, looking by turns sulky and scared.