Count Mattoni is brutally murdered and Scotland Yard Inspector Davidson must wade the through a myriad of suspects.
| Name | Type | Role | |
|---|---|---|---|
| Francis Cockrell | Writer | ||
| Alec Coppel | Writer | ||
| Patricia Hitchcock | Guest Star | ||
| John Williams | Guest Star | ||
| Anthony Dawson | Guest Star | ||
| Charles Cooper | Guest Star | ||
| Jered Barclay | Guest Star | ||
| Melville Cooper | Guest Star | ||
| Alan Napier | Guest Star | ||
| Kendrick Huxham | Guest Star | ||
| Charles Davis | Guest Star | ||
| Arthur Gould-Porter | Guest Star | ||
| George Pelling | Guest Star | ||
| Robert Stevens | Director |