No 12185, Monday 11 Dec 2017, Afterdark

ACROSS
1   Drinking aids found on street by intelligence agency sleuths at last (6) STRAWS {ST}{RAW}{s...hS}
4   Drops off fish returned on second thought (6) SLEEPS {EELS<=}{PS}
9   A man in pound? No an animal (4) LAMB {L{A}{M}B} (Addendum - {L{A}{Man}B} - See comments)
10 Swish, dance in a frenzy to get food, maybe (10) SANDWICHES*
11 Clean cutlery, has a hole holding bagels essentially (6) SPONGE {SPoON}{baGEls}
12 I've left management — editor enforced (8) EXECUTED {EXECUTive}{ED}
13 Nation of men and officer leading with integrity (9) COMMUNITY {CO}{MM}{UNITY}
15 Lives steady, oddly in ship (5) STAYS {S{sTeAdY}S
16 Leader seeking company at Pondy, say with escort (5) SCOUT {Se...g}{CO}{UT}
18 Unit killing heartlessly (9) ?I?O?R?M? Left for any commenter to solve and annotate (Addendum - KILOGRAM - {KillinG}=KG=KILOGRAMS - See comments)
22 Programme to develop farm plot (8) PLATFORM*
23 Class seen in lady, one in fancy house (6) POLISH {PO{L}{1}SH}
25 Settlers having onset of malignant melanoma in eyes reportedly get concessions (10) IMMIGRANTS {I{Ma...t}{Me...a}I}{GRANTS}
26 Part of egg yellow, organic lecithin kills primarily (4) YOLK Acrostic
27 Arrangement is to stay hungry before shoot (6) SYSTEM {StaY}{STEM}
28 Grown-ups, these days have uncontrollable lust (6) ADULTS {AD}{LUST*}

DOWN
1   Police officer consumes meat and eggs before cleaning (7) SHAMPOO {S{HAM}P}{OO}
2   Bird gives out — opening batsman gets a nick (edge) (5) ROBIN {RO}{Ba...n}{1}{Nick} RO for Run out?

3   Occidental woman enters with a bang (7) WESTERN {W}{ENTERS*}
5   Attorney at Los Angeles gutted with worry and hesitation (6) LAWYER {LA}{WorrY}{ER}
6   Having fenni regularly and taking a stand leads to fight (9) ENCOUNTER {fEnNi}{COUNTER}
7   Crack in screen leads to funny result in view (7) SCENERY {SCREEN*}{f..nY}
8   Arrive with stigma of hooking men for fun (13) ENTERTAINMENT {ENTER}{TAIN{MEN}T}
14 Fantastic, no tsunami can reach here (9) MOUNTAINS &lit
17 Articles with 100/0 units of flux discharge energy (7) COLUMNS {C/0}{LUMeNS}
19 Proposed action to drop resistance is antithetical (7) OPPOSED PrOPOSED*
20 Strength of donkeys is in their consumption of school certificate (7) MUSCLES {MU{S}{C}LES}
21 Stock Exchange implements B2C policy (6) COURSE (-b+c)COURSE
24 Firm alloy fused (5) LOYAL*

GRID