As the lounge reels from Judd Dodge's poisoning, a ninth person enters: a nervous, unassuming man in his twenties who introduces himself as Reginald "Reggie" Davis. Alarmed by the corpse, he tries to retreat, but Anna Matheson stops him, questions his presence, and demands identification. Reggie claims he mistakenly boarded the Phoenix while aiming for Baltimore, shows a Philadelphia-to-Baltimore ticket, and says he hid in a coach lavatory in panic until hearing others moving through the train.

Anna explains her identity, her father's framing, the conspirators aboard, and the express run to Chicago without stops. Reggie asks direct questions about Judd's death and whether Anna is responsible; Anna denies it and insists the killer is among those present. Dante Wentworth and Jack Lapsford disavow guilt, while the room’s suspicion remains unresolved.

Reggie suggests Judd might have poisoned himself rather than face prison, noting Judd’s isolation at the bar before collapsing. Anna considers the logic and orders Seamus to search the body for evidence of self-poisoning. Seamus finds only a pocket watch; no poison or container is discovered, returning the group to the conclusion that someone else poisoned Judd.

Concerned about further violence, Anna orders everyone to their rooms until Chicago and offers Reggie an empty first-class room, allowing him to retrieve his bag from coach. The conspirators object, demanding Anna and Seamus be searched in turn. Anna refuses to be searched by the conspirators and, when Reggie returns, asks him to pat her down as a neutral party.

During the frisk, Reggie discovers but does not reveal a knife strapped to Anna’s thigh, publicly declaring she is not concealing anything. Seamus displays only a watch and his revolver; Anna keeps the gun with Seamus despite Reggie and Lapsford’s objections to a firearm onboard. Anna reasserts that the plan’s rules apply to everyone, including Reggie.

Pressed about his safety, Reggie is told he must remain with the group and will be taken to a room to lock himself in. Seamus is assigned to escort him and check in periodically. As they depart, Anna silently questions Reggie's motives and why he concealed her weapon, but keeps him in first class under watch as the group prepares to isolate until arrival.