The Rats of NIMH is a trilogy of children's books, the first one by Robert C. O'Brien, and the second and third by his daughter Jane Leslie Conly. They tell the story of a society of rats rendered intelligent by scientific experimentation.
The books are:
Mrs. Frisby and the Rats of NIMH (1971), by Robert C. O'Brien, winner of the Newbery Medal
Racso and the Rats of NIMH (1986), by Jane Leslie Conly
R-T, Margaret, and the Rats of NIMH (1990), by Jane Leslie ConlyIn 1982, Mrs. Frisby and the Rats of NIMH became the basis for the animated film The Secret of NIMH, directed by Don Bluth. In 1998, a film sequel to The Secret of NIMH, called The Secret of NIMH 2: Timmy to the Rescue was released. The sequel has no connection to Jane Leslie Conly's sequel, Racso and the Rats of NIMH.
Variety announced in January 2017 that James Madigan would direct a live-action/animated reboot.
Read more or edit on Wikipedia