Cast
- Memo Benassi as John Brown, il detective
- Leda Gloria as Anna
- Giuditta Rissone as Alice
- Ninì Dinelli as Clara
- Lamberto Picasso as Fersen
- Ernesto Sabbatini as Ammiraglio Morstan
- Mino Doro as Carlo
- Fosco Giachetti as Raythan
- Alexandre Mihalesco as Jackie
- Oreste Fares as Mister Baskerville