Hearts not moving in one direction (9)
I believe the answer is:
northeast
'one direction' is the definition.
(northeast is a kind of direction)
'hearts not moving' is the wordplay.
'moving' indicates anagramming the letters.
'hearts'+'not'='heartsnot'
'heartsnot' with letters rearranged gives 'NORTHEAST'.
'in' is the link.
(Other definitions for northeast that I've seen before include "Bearing of 45 degrees" , "No threats (anag.)" , "Compass point at 45 degrees" , "Bearing of forty-five degrees" , "Belfast is located here" .)