You Call That Help? solution
by Kegler

Per 24 Across, THANKS FOR NOTHING, ten answers replace “nothing” (O) with “thanks” (TA).

You Call That Help? solution grid

Across
1ETHICISTS (THIS SECT I anag)
8RESORT (2 defs) {RESTART}
13WAR + N
14ORCA (1st letters)
16FLEA ("FLEE" hom)
17STOMA (A MOST anag)
18S(OD + I)UM (I DO rev) {STADIUM}
19I + G(LOt)O
21AR(GUn)ES
22MIA (2 defs)
24THANKS FOR NOTHING
26gETS
28SNIPER (rev)
31E + TUDE (DUET anag)
32K(E + RAT)IN
33V + IO + L {VITAL}
35E + XES (SEX anag)
36RETE (hidden)
37IN(N)S
38DENOTE (NEED TO anag) {DENTATE}
39ISRAELITE (REALITIES anag)
Down
2OUGHT (TOUGH anag) {TAUGHT}
3INTONERS (SINNER TO anag)
4COOk
5IR(M)A
6SCARF (2 defs)
7ON + GO(I)NG (NO rev) {TANGOING}
8RITE ("RIGHT" hom)
9ERA + S (ARE anag)
10SE + DATE
11ALUM (MAUL anag)
12ONAGERS (ORANGES anag) {TANAGERS}
13W(HIT)E + NED
15USURPERS (PURSUERS anag)
16F(ISH)OIL (HIS anag) {FISHTAIL}
20OKS + AN + A
23IN + DEN + T
25NEVE + R
27SEEN ("SCENE" hom)
28SOT (odd letters) {STAT}
29NICE (2 defs)
30tRIO {RITA}
34TEE (2 defs)