SLEUTH starts off the week with a great puzzle!
Our first SLEUTH blog, and most enjoyable it was too.
A lot of well constructed anagrams (PARLOUR GAMES, FILM STAR, NOMENCLATURE) and some great surfaces. LIAISE took us longer than it probably out to, and LEFT BANK was our LOI.
Thanks SLEUTH!

Across
1 Forge lies around capital to make contact (6)
LIAISE
(LIES)* (*forge) around AI (capital, A1)
4 Cruise, say, firm last organised (4,4)
FILM STAR
(FIRM LAST)* (*organised)
9 Vain fellow with posh hat (6)
FUTILE
F (fellow) with U (posh) + TILE (hat)
10 Democrat fronts institute in large-scale medical emergency (8)
EPIDEMIC
DEM (Democrat) + I[nstitute] (fronts) in EPIC (large scale)
12 Fix difficult situation (4)
BIND
Double definition
13 Old woman regularly ordered substantial part of meal (4,6)
MAIN COURSE
MA (old woman) + IN COURSE (regularly ordered)
15 Neater column arranged for list of names (12)
NOMENCLATURE
(NEATER COLUMN)* (*arranged)
18 Chap with future car in production? (12)
MANUFACTURER
MAN (chap) with (FUTURE CAR)* (*in production) &lit
21 Opening to trendy house in a crude form? Quite (10)
THOROUGHLY
T[rendy] (opening to) + HO (house) + ROUGHLY (in a crude form)
22 Cotton on part of a tree (4)
TWIG
Double definition
24 Second male in Switzerland with song showing magnetism (8)
CHARISMA
(S (second) + M (male)) in (CH (Switzerland) with ARIA (song))
25 Enthusiastic study into ballet, say (6)
ARDENT
DEN (study) into ART (ballet, say)
26 Render best work by magazine about island (8)
OPTIMISE
OP (work) by TIME (magazine) about IS (island)
27 Trophy retained by youngster? Totally true (4,2)
SPOT ON
POT (trophy) retained by SON (youngster)
Down
1 Quit institution that funds intellectual environment? (4,4)
LEFT BANK
LEFT (quit) + BANK (institution that funds)
The Left Bank was a district of Paris frequented by artists
2 A universal award encapsulating another for independence (8)
AUTONOMY
A U (universal) + TONY (award) encapsulating OM (another award, order of merit)
3 Soprano, sort in fine material (4)
SILK
S (soprano) + ILK (sort)
5 Enigmatic writer into malt beer I suspect (12)
IMPENETRABLE
PEN (writer) into (MALT BEER I)* (*suspect)
6 Credit boy I’m reforming losing last of drab uninspiring nature (10)
MEDIOCRITY
(CREDIT [b]OY IM)* (*reforming, losing [dra]B (last of))
7 Quality of sound in wood slightly adjusted (6)
TIMBRE
TIMBER (wood, slightly adjusted)
8 Element in firework display gets severe reprimand (6)
ROCKET
Double definition
11 Diversions for a house party making super alarm go off (7,5)
PARLOUR GAMES
(SUPER ALARM GO)* (*off)
14 Worker with a gadget endlessly around side produces hostility (10)
ANTAGONISM
ANT (worker) with A GISM[o] (gadget, endlessly) around ON (side)
16 Bully beginning to badger line on patrol (8)
BROWBEAT
B[adger] (beginning) + ROW (line) on BEAT (patrol)
17 Scare conservative in part of Cambridgeshire (8)
FRIGHTEN
RIGHT (conservative) + in FEN (part of Cambridgeshire)
19 Old clubs facing economies held up decorative work (6)
STUCCO
(OC (old clubs) facing CUTS (economies))< (<held up)
20 Drinking haunt in sweltering island capital (6)
HOBART
BAR (drinking haunt) in HOT (sweltering)
Hobart is the capital of Tasmania
23 Stagehand curtailed complaint (4)
GRIP
GRIP[e] (curtailed complaint)
After the long anagrams, the simplicity of SILK was a breath of fresh air.
Thanks Sleuth and Teacow
A surprise start to the week … but a welcome one, which took me twice as long as it normally does for a Monday puzzle ! Felt like doing four mini-crosswords in each corner with only the long anagrammatical clues to bind them together.
Never expect Australian answers, so HOBART took longer than it should have to show up as the island capital. Saw the Fens come up recently in relationship to Lincolnshire and didn’t realise that they spread into Cambridgeshire and Norfolk as well.
Sounds like I finished in a similar manner as the blogger with LIAISE, LEFT BANK and BIND my last few in.
I was held up by having entered PANDEMIC (dem in panic) for 10ac so had trouble with imPenetrable.
Thanks to Sleuth and Teacow. Lots of fun. I did not know ROCKET as reprimand and did not link AI to “capital” in LIAISE but otherwise proceeded smoothly.