Behold, Here's Poison written by Georgette Heyer performed by Ulli Birve on CD (Unabridged)

It's no ordinary morning at the Poplars – the master is found dead in his bed, and it seems his high blood pressure was not the cause. When an autopsy reveals a sinister poison, it's up to the quietly resourceful Inspector Hannasyde to catch the murderer in time to spare the next victim.

But every single member of the quarrelsome Matthews family has a motive and none, of course, has an alibi.