Drag queen quits Blackpool attraction (3)
I believe the answer is:
Here is my best explanation:
'drag' is the definition.
(towing is a kind of dragging)
'queen quits blackpool attraction' is the wordplay.
'queen' becomes 'er' (abbreviation for Elizabeth Regina).
'quits' indicates named letters should be taken away.
'blackpool attraction' becomes 'tower' (Blackpool Tower).
'tower' with 'er' taken away is 'TOW'.
(Other definitions for tow that I've seen before include "Drag along behind, say barge", "Pull (with rope)", "Prepared fibres", "Pull along (a vehicle)", "Haul", "form of flax", "Pull using cable", "Pull along behind, say barge", "Pull or drag along behind" and "Draw".)