Wild bloke in charge (5)
I believe the answer is:
manic
'wild' is the definition.
(I've seen this before)
'bloke in charge' is the wordplay.
'bloke' becomes 'man' (I've seen this before).
'in charge' becomes 'ic'.
'man'+'ic'='MANIC'
(Other definitions for manic that I've seen before include "Unnaturally excited" , "Pathologically excited" , "crazy" , "Obsessive" , "on one!" .)