Finally Scotland Yard contracted somebody in charge with get up and go (7)
I believe the answer is:
dynamic
'with get up and go' is the definition.
'finally scotland yard contracted somebody in charge' is the wordplay.
'finally' indicates one should take the final letters.
'yard' becomes 'y'.
'contracted somebody' becomes 'nam' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in charge' becomes 'ic'.
The final letter of 'scotland' is 'd'.
'd'+'y'+'nam'+'ic'='DYNAMIC'
(Other definitions for dynamic that I've seen before include "Powerful and vigorous" , "Very active" , "Vigorous and go-ahead" , "Full of energy and ideas" , "High-powered" .)