What initially looked like a young woman's suicide, turns into a murder investigation and Supt. Blake has two suspects - the victim's husband and his own daughter.
| Actor | Role |
|---|---|
 André MorellSupt. Blake | Supt. Blake |
 Thea GregoryJoan Blake | Joan Blake |
 Patrick HoltTerry Maguire | Terry Maguire |
 Jack WatlingBill Howard | Bill Howard |
 Marla LandiSinger | Singer |
| AArnold BellInspector Harris | Inspector Harris |
| OOlive SloaneMrs Pullman | Mrs Pullman |
 Bruce BeebySgt Fred Baker | Sgt Fred Baker |
 Alexander GaugeArnold Debenham | Arnold Debenham |
 Ellen PollockMme Sonia | Mme Sonia |
| DDorinda StevensNorma Sheridan | Norma Sheridan |
 Charlie DrakeJoe | Joe |