Bob, perhaps, and Ruth involved with CIA (7)
I believe the answer is:
haircut
'bob perhaps' is the definition.
(bob is a type of haircut)
'ruth involved with cia' is the wordplay.
'involved with' indicates anagramming the letters (involved can mean confusing or complex).
'ruth' anagrammed with 'cia' makes 'HAIRCUT'.
'and' acts as a link.
(Other definitions for haircut that I've seen before include "Bob possibly" , "Short back and sides?" , "that Damocles would have dreaded?" , "Salon service" , "Mohican, possibly" .)