Very straightforwardly clued, but with a nice sting in the tail. Nice one, Chalmie.

| Across | ||
| 8 | RUNT |
Smallest member of group not missing odd pieces (4)
Alternate letters of “GROUPNOT“ |
| 9 | EXPRESSION |
Manifestation of 6 openers in trouble (10)
An anagram (in trouble) of SIX OPENERS |
| 10 | EOCENE |
Electrical engineers once surprisingly parted when mammals appeared (6)
EE for electrical engineers parted by an anagram (surprisingly) of ONCE |
| 11 | NUCLEOLI |
Organelles – one I cull is defective (8)
An anagram (is defective) of ONE I CULL |
| 12 | TOMAHAWK |
Cruise missile heading for Tucson, an American city with weak walls (8)
T (first letter of Tucson) plus OMAHA plus WK, the outer letters (walls) of weak. |
| 14 | FASTEN |
Secure a way through marshland (6)
A ST (street, way) inserted into FEN |
| 16 | EIRE |
Heiresses maintain Ireland for the Irish (4)
Included in heiresses. Eire is the Irish name for the island of Ireland (ie what the Irish call it). |
| 17 | LAPEL |
Reading between the lines, copy part of coat (5)
APE (copy) inserted between L for line and L for line |
| 18 | DOHA |
Note a Gulf port (4)
DOH (the first note in tonic sol-fa) plus A |
| 19 | MENHIR |
People with time to surround the centre of big standing stone (6)
MEN (people) plus HR (hour, a period of time) around I (central letter of big) |
| 21 | SABOTEUR |
Regret coming back to boast about being someone who blows things up (8)
EUR (a reversal – coming back – of rue, or regret) prefixed by an anagram (about) of boast |
| 23 | ICE CREAM |
Mice race frantically to get dairy food (3,5)
An anagram (frantically) of mice race |
| 26 | SHINTO |
Secular humanist initially very appreciative of religion (6)
The initial letters of Secular Humanist plus INTO, an informal term meaning taking a lively and active interest in something |
| 27 | REQUISITES |
Risque ties could become essentials (10)
An anagram of risque ties |
| 28 | ESAU |
See biblical character make sausage sandwiches (4)
Included (sandwiched) in make sausage |
| Down | ||
| 1 | AUTOMOBILE |
Car one breaks out with phone (10)
A (one) plus an anagram (breaks) of out plus MOBILE as in mobile phone. |
| 2 | STEERAGE |
The cheapest cabins where it’s wise to accommodate support, right? (8)
SAGE (wise) accommodating TEE (support for ball) and R for right |
| 3 | TERESA |
Saint on the way up since before time began (6)
A reversal (on the way up) of AS (since) ERE (before) and T, the first letter (beginning) of time. |
| 4 | UPON |
Just above being well-informed (4)
To be up on something is an informal way of saying one is well informed about it. |
| 5 | PEACEFUL |
Quiet copper holds iron up during bell-ringing (8)
CU (copper) with EF (a reversal of FE – iron) inserted into it, in turn insertered into PEAL or ringing of a bell |
| 6 | ISLETS |
Archipelago – parts of it oddly silver inside (6)
ITS (of it) with the first, third and fifth letters of silver inserted. An archipelago is made up of islets. |
| 7 | DOLL |
Model on party lines (4)
LL (lines – again) on DO or party. |
| 13 | KEPIS |
Twisted spike’s headgear (5)
An anagram (twisted) of spike |
| 15 | EXHAUST FAN |
Use the last supporter’s ventilation equipment (7,3)
EXHAUST (deplete to zero) plus FAN (supporter) |
| 17 | LARGESSE |
Eelgrass cultivation produces a great deal to be distributed (8)
An anagram (cultivation) of eeelgrass |
| 18 | DETAINED |
Arrested foreign character having eaten out (8)
ETA, a letter of the Greek alphabet with DINED (eaten) outside it |
| 20 | HICCUP |
Involuntary noise greeting cricket club winning (6)
HI is the greeting; CC is cricket club, as in MCC; UP is ahead, or winning. |
| 22 | BASEST |
Most mean to get the upper hand when interrupting (6)
BEST (to get the better of) with AS (when) inserted (interrupting) |
| 24 | CREE |
Native American’s truncated statement of belief (4)
CREEd without its final letter. |
| 25 | MOTH |
One seeking light from university misses opening (4)
Mouth (opening) minus U for university |
Thank you David & Linda, I agree with you about the sting in the tail. Needed your help with the parsing of 25d – a lovely clue & so simple when explained!
Many thanks to Chalmie.
Check out the Nina round the outside of the puzzle! Well, Chalmie says it himself….
Steven, that’s what we meant by the sting in the tail.
Thanks for the blog D&L.
Since it appears to be me-day, I might as well say that my website is now up to Alchemi 200 and Hemical 93, if you get really bored and need something else to do.
Thanks for bringing Nina round, Michael. Nice one!
As usual, missed the Nina – good one, Chalmie. Memo to self: always look out for one (and stop using the excuse that it’s usually too early in the morning to be bothered with such niceties)!
Thanks Chalmie and D&L
A more gentle Chalmie than normal, but a lot of fun. A few new terms – NUCLEOLI / organelle and MENHIR (although maybe I have seen that before – only in another crossword though).
Finished in the left hand side with STEERAGE, AUTOMOBILE and MENHIR the last in.
Didn’t even think to look for the nina even though it was telegraphed with a grid like this.
Thanks D&L and Chalmie.
Nice one indeed. That’ll teach us!
Having read all the Asterix books when I was a lad, and having visited Carnac (the one in Brittany), MENHIR was a write-in.
Needed your help to parse 25dn. Though it’s obvious when you know.
Thanks to Chalmie for dropping in, even if it’s mainly to get the plug in.