The Lion and the Mouse was adapted from the well-worn stage play by Charles Klein. Lionel Barrymore stars as "Ready Money" Ryder, a ruthless businessman who destroys Judge Rossmore (Alec B. Francis), the father of heroine Shirley (May McAvoy). Soon thereafter, Ryder's weak-willed son Jefferson (William Collier Jr.) marries Shirley. Now that she's in a position of authority, the "mousy" Shirley gets even with "lion" Ryder by beating him at his own intimidation game. Originally released silent, Lion and the Mouse was reissued a few weeks later with talkie sequences. It is said that silent star May McAvoy's movie career was ruined because she had a pronounced lisp, but her voice registered quite well in the sound sequences; acting-wise, however, she was rather outclassed by those old barnstormers Barrymore and Francis.
by Hal Erickson synopsis