Saturday's client ordered a book case for a violinist (1,5,2,7)
I believe the answer is:
a study in scarlet
'a book case for a violinist' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'saturday's client ordered' is the wordplay.
'ordered' is an anagram indicator.
'saturdays'+'client'='saturdaysclient'
'saturdaysclient' anagrammed gives 'A STUDY IN SCARLET'.
Can you help me to learn more?
(Other definitions for a study in scarlet that I've seen before include "a brilliantly-coloured room" , "Work" , "colourful interior decoration for scholar?" , "detective story?" , "mystery" .)