Across:
1 Responsible for underground movement (SUBWAY) going back (= reversal indicator) on the road (bus = SUB-) to Washington (-WA-) on Fourth of July (fourth of ‘julY’= -Y) (SUBWAY),
4 Shows one’s appreciation (APPLAUDS) to a (A-) minister (parish priest = -PP-) at prayer service (-LAUDS) (APPLAUDS),
9 Turns up (= reverse indicator) before Easter (Lent = T-NEL) welcoming most of (j) the journalists (‘nuj’ without ‘j’ = nu = -UN-) (TUNNEL) with vision (TUNNEL vision),
10 Save (SALT AWAY) sailor (SALT) from taking a (A-) course (-WAY) (SALT AWAY),
12 Big Top Security protecting the swingers (SAFETY NET) with a guarantee in case one falls on hard times (SAFETY NET),
13 Review? (= reverse indicator) Salt (salt = -TLAS) away (A-) from the start (= position indicator) (ATLAS) for one of the titans! (ATLAS),
14 Opens 18 across (opens ‘Dutch auction’ = DUTCH) on local bottle (local ‘bottle’ = COURAGE) (DUTCH COURAGE) to drink (DUTCH COURAGE),
18 From Amsterdam (DUTCH) leave port (sail) hearing (= homophone indicator) (‘sail’ = ‘sale’ = AUCTION) (DUTCH AUCTION) prices will gradually fall here (DUTCH AUCTION),
21 A (A-) key (music key -B-) opens outside door entering (opens ‘Outside Door Entering’ = -ODE) (ABODE) the house (ABODE),
22 This is all I’m going to say on this (ULTIMATUM) and you can take it or leave it? (ULTIMATUM),
24 Sign (-V- sign) in laconic (laconic) rework (= anagram indicator) (laconic = -OLCANIC) (VOLCANIC) that one is incredibly unstable and likely to explode (VOLCANIC),
25 Panellist misses pal (‘panellist’ misses ‘pal’ = nelist = SILENT) still (SILENT),
26 Rips through the script, page-by-page (SHREDDER), for one of those making cuts in The Office (SHREDDER),
27 Position (STATUS) of peers from super states (‘peers’ from ‘super states’ = sutats = STATUS).
Down:
1 One of those from the stage (SET-) heard by the audience (aside = -ASIDE) (SET-ASIDE) is put away (put away = SET-ASIDE),
2 Beef isn’t (beef isn’t) bad (= anagram indicator) (beef isn’t = BENEFITS) and does you good (BENEFITS),
3 Representative (AGENT) gets along with logs (‘gets along’ with ‘logs’ = getan = AGENT),
5 Copies (PLASTER CASTS) produced by Band Aid (band aid = PLASTER) and lots of players (CASTS) (PLASTER CASTS),
6 Slow (LETHARGIC) to use (= anagram indicator) the garlic (the garlic = LETHARGIC),
7 Sick (UNWELL) of you and I (-WE-) following (= position indicator) foreign article (a = UN-) line (-L-) by line (-L) (UNWELL),
8 The most reserved (SHYEST) call for silence? (SH-) Certainly (-YES-), it’s time! (-T) (SHYEST),
11 Headless (g) spirit (‘gin’ without ‘g’ = IN-) is beyond a shadow of doubt (-CONCLUSIVE) (INCONCLUSIVE) still open to question (INCONCLUSIVE),
15 Domestic (HOUSEMAID) legislative body (HOUSE-) open-minded (open ‘Minded’ = -M-) to help (-AID) (HOUSEMAID),
16 Clip (e) of Holly (tree) (‘tree’ without ‘e’ = -TRE-) getting answer (-A-) in The Cloud (the cloud = mist = MIS-T) (MISTREAT) leads to abuse (MISTREAT),
17 Breathes new life into (ANIMATES) mates in a (mates in a) production (= anagram indicator) (mates in a = ANIMATES),
19 Victor (-V-) is in low-lying areas (VAL-ES) (VALVES) controlling the distribution of water (VALVES),
20 Upsets (= reversal indicator) everyone (all = -LLA-) in bar (rod = DO-R) (DOLLAR) in foreign capital (foreign capital/money = DOLLAR),
23 Sweaty (MOIST) heartless (a) chairman (‘Mao’ without ‘a’ = MO-) is (-IS-) starting trouble (starting ‘Trouble’ = -T) (MOIST).