Kildare tries brain surgery, advised by Dr. Gillespie, and faces a rival for nurse Lamont.
| Actor | Role |
|---|---|
 Lew AyresJames Kildare | James Kildare |
 Lionel BarrymoreLeonard Gillespie | Leonard Gillespie |
 Laraine DayMary Lamont | Mary Lamont |
 Shepperd StrudwickGregory Lane | Gregory Lane |
 Samuel S. HindsStephen Kildare | Stephen Kildare |
 Emma DunnMartha Kildare | Martha Kildare |
 Nat PendletonWayman | Wayman |
 Walter KingsfordSJ Carew | SJ Carew |
 Alma KrugerMolly Byrd | Molly Byrd |
 John EldredgeHenry Adams | Henry Adams |
 Nell CraigNosey | Nosey |
 Marie BlakeSally | Sally |
| CCharles WaldronEgghead' Squires | Egghead' Squires |
 George LesseyRufus Ingersoll | Rufus Ingersoll |
 Tom CollinsJoiner | Joiner |
 George H. ReedConover | Conover |
 Paul PorcasiAntonio | Antonio |
 Horace McMahonFog Horn | Fog Horn |
 Frank OrthMike | Mike |
 Margaret SeddonMrs. Cray | Mrs. Cray |
 Fay HelmMrs. Adams | Mrs. Adams |
 William BaileySpectator in Operating Theatre (uncredited) | Spectator in Operating Theatre (uncredited) |
 Stephen ChaseAmbulance Intern (uncredited) | Ambulance Intern (uncredited) |
 Donald DouglasMr. Grayson (uncredited) | Mr. Grayson (uncredited) |