According to The Hollywood Reporter, Paramount will be releasing a "Mrs. Frisby and the Rats of NIMH" film, based on the book by Robert C. O'Brien.
This will be the second adaptation of the novel. In 1982, "The Secret of NIMH" was released, based on the book. It followed a mouse, Mrs. Brisby (changed due to copyright fears), who needs to move her family due to the threat of a field plow. She faces adversity when her son falls ill.
No definite word if the film will be animated, or a live action/animation combo, but it is rumored to be the latter.