First murderer keeps bishop in hut (5)
I believe the answer is:
cabin
'hut' is the definition.
(I've seen this before)
'first murderer keeps bishop' is the wordplay.
'first murderer' becomes 'cain' (I've seen this before).
'keeps' is an insertion indicator.
'bishop' becomes 'B' (abbreviation used in chess).
'cain' placed around 'b' is 'CABIN'.
'in' acts as a link.
(Other definitions for cabin that I've seen before include "Small house (built of logs?)" , "Shipboard room" , "Wooden shack" , "Marine digs" , "Building" .)