Jennings founds the Linbury Court Detective Agency, tracks a suspected burglar to his thieves' kitchen, sees mysterious lights in the sanatorium, and solves the burglary of the trophies from the library on Sports Day.
|Jennings (John Jennings)||10||John Christopher Timothy Jennings - father is a businessman and home is Haywards Heath. Main character in all books.|
|Derbi (Charles Derbyshire)||10||Charles Edwin Jeremy Derbishire - son of a clergyman (Rev. Percival Derbishire). no 2 to Jennings, rarely the instigator, but instead faithful follower.|