Jacques Lantier, the "human beast" of the title, has a hereditary madness and has several times in his life wanted to murder women. At the beginning of the story he is an engine driver, in control of his engine "La Lison". His relationship with "La Lison" is almost sexual and provides some degree of control over his mania.
| Actor | Role |
|---|---|
 Ossip RunitschJacques Lantier | Jacques Lantier |
 Maria OrskaNot listed | Not listed |
 Ilka GrüningNot listed | Not listed |
 Lucie HöflichNot listed | Not listed |
| EEduard von WintersteinNot listed | Not listed |
| HHugo DöblinNot listed | Not listed |