Bill is a paranoid survivalist and mechanic who lives alone in Lincoln, a town he has rigged with traps against the infected. He owes Joel favors from their smuggling deals, so in Bill's Town Joel asks him for a car, and Bill joins you to find the parts.
Joel has never actually been to Lincoln, so he and Ellie stumble through Bill's barricades and set off his traps. A snare leaves Joel hanging upside down while Ellie cuts him free and runners swarm in, until Bill arrives and saves them. In the safe room he knocks Joel down and cuffs Ellie, convinced they might be bitten, before agreeing to build a car on condition that it settles every favor he owes.
The chapter runs through the woods, Bill's safehouse, the graveyard and the high school. Bill fights beside you with his shotgun and trades insults with Ellie the whole way. The battery he was counting on is gone from the crashed military truck at Lincoln High School, and you have to fight a bloater to get out the back.
Ellie finds a truck in a garage with the missing battery inside. It is drained but the cells are good, so Bill and Joel push it through the streets past infected while Ellie pops the clutch. Back at the church Bill tells Joel they are square and orders them out of his town.
Bill once had a partner, Frank, and lectures Joel that caring for someone only gets you killed. On the way back from the school they find Frank hanging in a house: he was bitten and killed himself, leaving a note saying he hated Bill. Frank had taken the battery for his own truck. Bill brushes it off, but the loss clearly hits him.
Frank
Frank is Bill's former partner in Lincoln. You learn about him in Bill's Town through the Note from Frank, and he also turns up earlier in The Outskirts as the contact named in a smuggler's note.
Ellie Williams
Ellie Williams is the 14-year-old girl Joel is hired to smuggle out of Boston, and your companion for most of The Last of Us Part I. She was bitten weeks earlier and never turned, so the Fireflies believe her immunity could lead to a vaccine. You play as her in the winter chapter and in the Left Behind DLC.
Joel Miller
Joel Miller is the man you play for almost all of The Last of Us Part I. A hardened smuggler in the Boston quarantine zone, he takes a job escorting 14-year-old Ellie out of the city, and the drop-off turns into a year-long trip across the country to find the Fireflies.