Dr Sanada (Takashi Shimuira) the drunken angel of the title runs a clinic in the slums of Tokyo. When small-time hood Matsunaga (Toshiro Mifune) comes to his surgery after a gunfight Sanada diagnoses him with tuberculosis and convinces him to begin treatment. The disillusioned doctor feels that by saving this young yakuza he can retrieve a sense of his own lost youth and idealism. Thus they embark on a troubled friendship which is tested by the prejudices of the two and the release from prison of Matsun..
