Cryptic crossword No 3,942

Across

1. Study about a party in Ulster (4,2)
2. Upset when a nasty piece of work got put away (7)
3. Look round and look down in front of soprano singer (2,4,4)
4. Book concealed in jotter Bill brought back (8)
5. God, God I need houses (4)
6. Thin 20 with instrument (6)
7. Royal at home with cold besieged by media (8)
8. Austere purpose of auction room (10)
9. Rat on posh criminal (4)
10. Brave Ms Stubbs' strong bust (8)
11. Reportedly, d-descendants to break away (6)
12. In Pakistan, Karachi is capital? (6)
13. Quiet city has university? Lies! (7)
14. What manufacturer wants to shorten is the French commercial - release pushed back (4,4)

Down

1. Drastic action taken about Roman Catholic supplying drug (8)
2. Like heavy metal produced when Bill replaces the injured Don in Osmonds (7)
3. Father's horse (4)
4. I put on plaster after getting cut bottom, or was it more hip? (8)
5. Press club (4)
6. Nice fishsticks (8)
7. Good man to dress in flash (6)
8. Cat heard hat is fair game? (7)
9. Ponder problem, having lost illegitimate son of Victoria and Albert, perhaps (6)
10. Sibling you finally ditch - what a fuss! (8)
11. Astounded by report of animal transport in East London (9)
12. Established what you might learn by eating duck with duke (6)
13. Oddly, Alex, Greg, Anna and you can find Hydra here! (6)
14. Aunty sent sables, skinned? It's indefensible (9)