The two-hour pilot "Serenity" also featured a scene in Simon's cabin with him and Zoe: he's listening to an encyclopedia entry on the Battle of Serenity Valley, from which the ship gets its name, and she comes in and gives an eyewitness account of it, from Mal commanding over 2000 people after a week due to high officer casualties, to both sides stacking corpses for cover, to medical relief for both sides being held back for a week after a cease-fire was declared, to her and Mal being the only survivors of their platoon, and that she'd kill Simon on a word from Mal.