Chapter 21

An Obvious Trap (えいた) is the twenty-first chapter of The Promised Neverland manga.

Plot
The chapter starts with a shocked young Krone (who was expecting to meet her adopted family) in front of a demon in the Gate. Her Mama was along with her.

However, too terrified of dying, she accepted the proposal of becoming a Mama. The next scene shows her with Grandmother and some other children. Grandmother was talking to Krone.

The next panel starts the main story. Emma and Norman entered Sister Krone's room to question her. Since Emma and Norman had prepared their questions beforehand. Emma demands that she show them that. Sister Krone lends them the tracking device. Norman and Emma took a good look on it. Sister Krone reveals the location of the trackers, which are located somewhere in the left ear. They discuss about it for some time before moving on to the next question.

Emma asks about Sister Krone's age, and she answers her. Sister Krone also told them that she was born and raised in Grace Field House. She also reveals Isabella's age, 31.

Later, Norman asks about the outside world, but unluckily, Sister Krone hasn't seen it. However, it is revealed that humans do exist outside and she saw a human once in the Headquarters. Emma then assumes that there is a higher possibility that William Minerva could still be alive if this is true.

Emma and Norman then asked their separate questions but Sister Krone didn't have the answer. Norman then asks about the security, to which Sister Krone replied that it wasn't very strict. However, Norman and Emma believe this to be a lie.

Emma and Norman then prepare to leave. However, as soon as they are to open the door and leave, Sister Krone laughs viciously to which Emma and Norman are utterly shocked.

Sister Krone starts to make fun of them, telling them that they failed to question her properly. Emma and Norman are left in dismay, because they were convinced that they had prepared for everything before entering the room. However, Sister Krone explained to them she came to know about their plans through their expressions. Both of the children get frustrated.

When Sister Krone had said enough, Emma and Norman started to leave one again. However, Sister Krone stopped them by asking whether they knew of the Demon Boss. However, their surprised expressions told they didn't. Sister Krone says that she'll tell them about the Demon Boss the next time they come over to question.

As they leave the room, both of the children discuss with frustration. They agree with the fact that tomorrow's investigation must be a success to get out of the Grace Field Plantation.

Meanwhile, on Thursday, November 2nd, where there only 6 days left for the escape, Mama Isabella finally makes her move.

Research Elements
In this chapter we have the following Research Elements:
 * Adults like Sister Krone and Isabella who come from farms produce food for the demons. But there are also people from the 'outside' world who produce and deliver all of their clothes and other supplies like toys, furniture et cetera.