Across: 7. May playing guitar develop brain? (5) 9. Usual introduction in arrangement of any Lorde song (9) 10. May the cape's state by end of Superman see Jewry upset? (3 6) 11. Most deer dance (5) 12. Parent at religious festival to look back (5) 13. Two metals blended as rod in storage facilities (9) 15. May fly like the ape emperor, beaten (13) 19. May I look with an unusually keen eye, espying openings to city? (9) 20. May the isle be found in Firth of such? (Foremost of rivers that have mouths therein.) (5) 22. May the force... (5) 23. ...be lost in leaders controlled by aggressive drug retailer who provides the literature? (9) 24. Ruing ale - a problem which may hit a nerve (9) 25. May writing and drawing give imagined "bush babies" Sydney origins? (5) Down: 1. Carefree spirit when pub has this? (7) 2. Regarded as struggle in marriage (6) 3. Verify foul on the rink (10) 4. May not have twelve peers changing sides (4) 5. May the cape's bay elude law, a regional hideaway? (8) 6. Dead Kennedys holiday here as agitated mob help coming up with "California Über Alles" (8) 8. May the war be over, finally contained by Northeast African statesman (7) 14. Spin in preference to bold ideas and legitimate leadership, as it is said (10) 15. Structures partially obscured if ice settles (8) 16. May strange thaw come before part of Northeast Africa? (8) 17. Inappropriate gift containing illegally harvested shark part causes argument (7) 18. May a political leader put that place before South Africa? (7) 21. Freebaser overwhelms hospital treatment programs for addiction (6) 23. Frank Zappa had a black one; Led Zeppelin had a white one (4)