Auntie Shrew

Auntie Shrew is the quinary antagonist later anti hero in the Secret of NIMH. She is the baby-sitter for Mrs. Brisby's children, though she does not seem to like Martin much because of his impudence, and self-appointed community leader for the animals in the garden. She also used to be jealous of Brisby until she reforms to help her turn off the plow. She was voiced by the late Hermoine Baddeley.

Personality
Auntie Shew is a nosy, close-minded busybody who takes it upon herself to ensure that all the wild animals on the farm are safe, even to the point of intrusiveness. While vicious and hostile, she has good intentions, wanting only to ensure the safety of her friends and neighbors, especially the meek Mrs. Brisby. She seems to be hard of hearing, or simply too wrapped up in her own melodramatic air that she needs to be repeatedly told things before acknowledging them, as with Mrs. Brisby's children repeatedly telling her that their mother is not home and that Timmy is sick. Despite all this, she also seems to be quite athletic as well when it came to stopping the plow.

Role in Film
Auntie Shrew is the one who shouts at all the animals to evacuate the field in order to escape the coming plow. When it threatens to destroy Mrs. Brisby's home, she jumps into the plow to sabotage the fuel injector and buy them more time. She also suggests asking the Great Owl for advice.

Trivia

 * Despite being called Auntie, she is clearly not related to the Brisbys, as she is not the same species. Likely, the term, "Auntie," is a term of respect and endearment.
 * She seems to be bigger than Brisby's kids (especially Teresa), but quite smaller to Mrs. Brisby. Despite this, Shrew is as mean as Brisby is kind, as obese as Brisby is slender, and as hideous as Brisby is lovely.
 * She is commonly mistaken as the main antagonist.  However, Jenner is the main antagonist since Shrew only makes a few appearances throughout the movie, plus Jenner had bigger plans than anyone else.