They Never Say When
First edition | |
| Author | Peter Cheyney |
|---|---|
| Language | English |
| Series | Slim Callaghan |
| Genre | Thriller |
| Publisher | William Collins, Sons |
Publication date | 1944 |
| Publication place | United Kingdom |
| Media type | |
| Preceded by | Sorry You've Been Troubled |
| Followed by | Uneasy Terms |
They Never Say When is a 1944 thriller novel by the British writer Peter Cheyney. It is the sixth in his series of novels featuring the London private detective Slim Callaghan, a British version of the increasingly popular hardboiled American detectives.