Ben

Joseph Campanella – Arthur O’Connell 1972
A lonely boy named Danny Garrison befriends the rat that leads the swarm of trained/telepathic rats found in Willard. This rat, whom the boy names Ben (after he hears about the leader of a flock of killer rats), becomes the boy’s best friend and keeps his spirits up in the face of bullying and his terrible illness..However, the balance of power between Danny and Ben begins to shift, with Ben beginning to control the boy and the swarm becoming increasingly irrational and violent. Ben becomes violent when the town folks used pesticide and killed his partner.

With Original Trailer