The unclued lights are to be resolved into four (unrelated, non-thematic) phrases which share a common format.

Across

12 Pope, maybe, as thespian turning in late in France (9, two words)

13 Pound fine imposed on Bill Stevenson (5)

15 Reserve WC in polar areas (9)

20 Cosseted artist in recording was dominant (7)

24 Alastair organised white-collar workers (8)

26 Key worker’s jargon (4)

27 Sash Holbein regularly displayed (3)

28 Either way, one in order (3)

29 Resistance units – I see thousands (4)

32 Collier’s outer garment covers vestment that’s old (8, two words)

34 Bull...