To recover from the uncontrollable anger, one went inside (6)
I believe the answer is:
regain
'to recover' is the definition.
('regain' can be a synonym of 'recover')
'uncontrollable anger one went inside' is the wordplay.
'uncontrollable' becomes 'i' (I am not sure about this - if you are sure you should believe this answer much more).
'one went' is an anagram indicator ('go' can mean move).
'inside' indicates putting letters inside.
'anger' with letters rearranged gives 'regan'.
'i' put inside 'regan' is 'REGAIN'.
'from the' acts as a link.
Can you help me to learn more?
(Other definitions for regain that I've seen before include "Get back (previously owned object)" , "Get back, recover the use of" , "Possess once more for regina" , "Recover, retrieve" , "Take back (the Ashes, for example)" .)