With only a few hours of oxygen left, Mal orders the crew to divide into two groups and head off in opposite directions in the Serenity's two shuttles, while he stays behind with the ship in case someone picks up their distress signal.
He offers to trade the captain anything in the cargo hold for a new catalyzer, but the salvagers shoot Mal in the chest and attempt to commandeer the Serenity for scrap.
Bleeding from a stomach wound and on the verge of passing out, Mal manages to get the new catalyzer installed and restarts the engine just as the ship's oxygen runs out.
Flashbacks are intercut with the two more recent timelines based on spatial relationships, contrasting past events in certain areas of the ship with current ones.
Mal then decides to hire out the Serenity's shuttles, and meets Inara Serra, who uses her high status as a Companion to bargain for a 25% discount on the rent.
Also according to the commentary, Gina Torres (Zoe) was written out of the bulk of the episode because the filming took place just after her marriage to Laurence Fishburne and they were away on their honeymoon.
[citation needed] Show creator and executive producer Joss Whedon lists "Out of Gas" as one of the "three favorite projects he's ever been involved in," the other two being a Buffy the Vampire Slayer episode and comic book.