"He risked his life to save a rat... And what did he get for it?"

Internes Can't Take Money

Dr. Kildare treats and falls for impoverished ex-con Janet Haley, widow of a bank robber, who can't find her baby. Later she helps Kildare sew up gangster Hanlon in a tavern back room. Kildare pursues Janet and enlists Hanlon to help her; the gangster's solution, not surprisingly, is violent.