Robert C. O'Brien has written at least 11 books. Their most popular book is Mrs. Frisby and the Rats of NIMH with 216 saves with an average rating of 4.11⭐.
Series
2 primary booksAuthored 50% of series
Rats of NIMH is a 2-book series with 2 released primary works first released in 1971 with contributions by Robert C. O'Brien, Jane Leslie Conly, and Leonard Lubin.