Mrs. Frisby, accompanied by Mr. Ages and Justin, meet Nicodemus. Engaged in an urgent meeting, Mrs. Frisby is requested by them to wait in the library, while she was in library, she reads a little bit about NIMH and she asked her self what is the NIMH. Driven by curiosity, she starts to scan this room and what is written on it Blackboard without being able to understand more paln.
During her cogitation about what may well be these strange rats and how do they have, among other things, electricity and books, Mrs. Frisby is joined by a young female rat which, at first, gasped to see Mrs. Frisby there, lets drop her papers on the floor.
A conversation begins, during which, the young rat named Isabella, recovered from her surprise and her suspicions towards Mrs. Frisby, replies to some of her questions: They come from a place called “NIMH” as well as her late husband and Mr. Ages. They are preparing a plan for which, women store grains and men are busy in a meeting. Nicodemus is their leader. And a rat named Jenner has deserted the group for mysterious reason , due likely to a disagreement with the others.
It is on this recapitulation of the gleaned informations that come into the library Mr. Ages, Justin, Nicodemus and another stranger rat.
Source : O'Brien, R.C (1971). Mrs. Frisby and the Rats of NIMH. New York: Aladin Paperbacks.