Russian car carrying detective's superior (2-2-2)
I believe the answer is:
la-di-da
'superior' is the definition.
'russian car carrying detective's' is the wordplay.
'russian car' becomes 'Lada' (Soviet Union car brand).
'carrying' indicates putting letters inside.
'detective' becomes 'di' (Detective Inspector abbreviation).
'lada' placed around 'di' is 'LA-DI-DA'.
(Other definitions for la-di-da that I've seen before include "Affectedly genteel" , "Pretentious, snobbish" , "Stuck-up" , "I'd a lad with affected manner or pronunciation" , "Hoity-toity" .)