Cryptic crossword No 2,795

Across

1. He conceals base instincts in disguise (4)
2. Duty to turn clock back (5)
3. Starts to scream or shriek in a cry for help (3)
4. Front of lorry missing back, back, back (3)
5. Maybe vampire lurks incubating? (3)
6. Finally, chill in spine that can describe 21a, 23a (especially at 1), 25a and 27a (5)
7. Come together for 1 season in America in best tie (4,4,5)
8. Enthralled by witch, all owe enchanted 24 or 25d today (9)
9. Devilish erotic clothing - one often in spandex tights (4)
10. Cause of inflation family is usually cut up about this time of year (7)
11. Partner of sin with belly dance finally in dress (7)
12. Taped creepy expert (5)
13. Beat guy genetically opposed to GTA? (3)
14. Hot stuff whose involvement would make S&M party finally steamy (3)
15. Alien grey spy abducting coward, expelling potassium with supernatural force (7,6)
16. Content of delivery for fair and party (7,4)

Down

1. Friendly topless friend (4)
2. Reacts in shock, losing head at slimy creatures (4)
3. Send a Brummie's mother off for spice (8)
4. Rubbed soap, but nothing dissolved in bath (3)
5. After refiguring: ninety, not nothing (9)
6. Simple like soda (5)
7. Prickly types around beginning of play (5)
8. Prematurely terminated pact of 24 or ...? (5)
9. Here, you'll find gladiators are North American (5)
10. Father abandoned enemy of snakes... or 25d? (5)
11. Catch fish - catch them with what? These aren't mobile (9)
12. Plan warehouse fight, some would say (8)
13. Disaster of Spooner's scourge ogre (9)
14. 23a that's small and uniform (3)
15. Demon ensnaring girl in ring - that can be seedy (5)
16. Rude-sounding fliers see courts detaining criminal leader in defendant's box (9)