Across:
1 Out of ideas (AT ONE'S WITS' END), deals with guilt ('atones' = 'at ones' = AT ONE'S) by going to last performance of The Comedians (last performance of The Comedians = WITS' END) (AT ONE'S WITS' END),
10 Trump (TR-UMP-) overshadowed first person (-I-) to tip Hillary (tip ‘Hillary’ = -H) (TRIUMPH) to win (TRIUMPH),
11 Make-up (= anagram indicator) artist (artist = TRA-SIT) welcomes new (-N-) (TRANSIT) shipment (TRANSIT),
12 Awful (= anagram indicator) risk (risk = IRKS) of bugs (IRKS),
13 Key (music key B-) to uncertainty (-RISK) (BRISK) produced by Swift (BRISK),
15 Some revolutionary (= reverse indicator) church seminaries (some ‘churcH SEMinaries’ = hsem = MESH) go well together (MESH),
17 Carry On (rant) without the lead (r) (‘rant’ without ‘r’ = ANT) – the one that’s a pest (ANT),
19 Poses (sits = SIT-S) around popular (-IN-) (SIT-INS) forms of civil disobedience (SIT-INS),
21 A (A-) single 19 across (single ‘sit-in’) isn’t finished (n) (‘sit in’ with ‘n’ = -S IT I-) outside Centre (‘outSide’ centre = -S) (AS IT IS) the way things stand (AS IT IS),
22 Prune (CUTBACK) top of tree (top of ‘Tree’ = -T-) in the country (Cuba = CU-BA-) with chainsaw primarily (‘Chainsaw’ primarily = -T-) on weekend (‘weeK’ end = -K) (CUTBACK),
23 Serves up (= reverse indicator) the foreign (el = -LE) food (grub) for the most part (b) (‘grub’ without ‘b’ = gru = URG-) with good (G-) (GURGLE) bubbly, by the sound of it (GURGLE),
25 Rasta left traumatised (‘rasta’ left ‘traumatised’ = tumied = TEDIUM) by boredom (TEDIUM),
27 Short cut perhaps (a BOB hair cut) leads to back of beyond (leads to ‘Back Of Beyond’ = BOB),
29 A bit pretentious (ARTY) from political organisation (party) dumping leader (p) (‘party’ without ‘p’ = ARTY),
30 One of those outside The House at the back (PATIO) with the Irishman (PAT-) from Number Ten (-IO)? (PATIO),
31 Sides with venture capitalist (sides with ‘VEnture capitaliST’ = VEST) taking the shirt off your back to expose this (VEST),
34 For the most part (d), it’s difficult (hard) (‘hard’ without ‘d’ = - HAR-) finding Bill (-AD-) Clare (CE = C-E) outside (CHARADE) pantomime (CHARADE),
35 Stole (TOOK) target? (AIM) (TOOK AIM) The sniper did it! (TOOK AIM),
36 For a (A-) time (-T), journalist working online (blogger) starting off (b) (‘blogger’ without ‘b’ = LOGGER-) directs (-HEADS) (AT LOGGERHEADS) violent disagreement (AT LOGGERHEADS).
Down:
2 Wild (= anagram indicator) kitten (kitten = T-INKET) picks up lead ring (lead 'Ring' = -R-) (TRINKET) of knick-knack (TRINKET),
3 Handle (NAME) employee savings plan set up (= reverse indicator) by the banks (‘EMployee savings plAN’ by the banks = eman = NAME),
4 I knew it (I knew it! = aha! = -AHA-) is never-ending (‘neveR’ ending = -R-) in South Africa (SA = S-A) (SAHARA) – a really hot place (SAHARA Desert),
5 A measure of the sharpness (IQ TEST) of talent spotter (IQ TEST),
6 Rock- (SWAY) -and-roll? (SWAY),
7 Just starting (NASCENT) with Norwegian leader (‘Norwegian’ leader = N-) going on trip to summit (-ASCENT) (NASCENT),
8 On the face of it (AT FIRST GLANCE), it’s a (A-) car (Model -T) for Irish men (Irish ‘men’ = FIR-) on the street (-ST) that’s flash? (GLANCE) (AT FIRST GLANCE),
9 Nevertheless (AT THE SAME TIME), it’s when you might see the witching hour in relation to midnight (witching hour + midnight = AT THE SAME TIME)
14 Link (link) adaptation (= anagram indicator) (link = INK-L-) about supporting film (-B- film) to good books (Old Testament = -OT) (INKBLOT) – that’s a test of the personality (INKBLOT test of personality),
16 Filthy (unclean) article (an) is removed (‘unclean’ without ‘an’ = uncle = UNCLE) by a family member (UNCLE).
18 A (A-) stitch-up (sew = -S-EW) over the weekend (over the ‘weeK’ end = -K-) (ASKEW) is out of kilter (ASKEW),
20 Seek redress (SUE) for reports coming out of superstore (‘reports’ coming out of ‘superstore’ = sue = SUE),
21 Heading for Appeal (heading for ‘Appeal’ = A-) Court (-CT) (ACT) to take the initiative (ACT),
24 Have another go at getting (retry) most (y) (‘retry’ without ‘y’ = RETR-) characters in 21 down (‘act’ = -ACT) (RETRACT) to withdraw (RETRACT),
26 Nice lad (nice lad) moving (= anagram indicator) (nice lad = ICELAND) to cool sounding place on the northside? (ICELAND),
27 What’s wrong (BAD) with The Force (-G force) following (= position indicator), for example (e.g. = EG-) (BAD EGG), scoundrel? (BAD EGG),
28 Drink (BITTER) it (-IT-) with starter of toast (starter of ‘Toast’ = -T-) in Belgium (B-E-) at the end of summer (end of ‘summeR’ = -R) (BITTER),
32 It’s over (= reverse indicator) oxygen (-O) and hydrogen, for example (gas = SAG-) (SAGO), produced by Palm raised in swamp (SAGO),
33 Carry a torch for (LOVE) hauling up (= reversal indicator) those inside active volcano (those inside ‘activE VOLcano’ = evol = LOVE).