One shifting up after film’s ending (5)
I believe the answer is:
mover
'one shifting' is the definition.
'up after film's ending' is the wordplay.
'up' becomes 'over'.
'after' says to put letters next to each other.
'ending' says to take the final letters.
The last letter of 'film' is 'm'.
'over' after 'm' is 'MOVER'.
(Other definitions for mover that I've seen before include "Dynamic type" , "Instigator, organiser" , ". . . . . and shaker, he or she wields power and influence" , "Someone who proposes a motion for debate" , "One who is in motion - may also be a shaker" .)