291045 is the forth episode of The Promised Neverland anime, released on January 31, 2019.
The episode opens with Mother giving Krone a cold warning to stay in her lane and to not attempt to undermine her. With that power struggle unknowingly happening in the background, Emma, Norman, and Ray continue to try to root out the traitor. Despite the risks, they agree to bring two other children, Don and Gilda, into their plans. Norman sets up a trap for the traitor with unlikely consequences.