Murderous brother keeping book in hut (5)
I believe the answer is:
cabin
'hut' is the definition.
(I've seen this before)
'murderous brother keeping book' is the wordplay.
'murderous brother' becomes 'cain' (I have seen 'Brother of Abel ' mean 'cain' so perhaps 'brother' could also mean 'cain'. I am not sure about the 'murderous' bit.).
'keeping' means one lot of letters goes inside another.
'book' becomes 'b' (abbreviation for book).
'cain' going around 'b' is 'CABIN'.
'in' is the link.
Can you help me to learn more?
(Other definitions for cabin that I've seen before include "Marine digs" , "Wooden hut" , "place on board" , "Small house (built of logs?)" , "Railway signal box" .)