1a) Like Circle Line's nerve-wracking conclusion? (5-6)
2d) First half of book's boring poetry and too wordy (7)
5d) R. Stein's staggering ads in magazines? (7)
10a) Acquit sailor on his own, jailing 5 (7)
12a) Plug from motor dismantled in gym (7)
Apology for no letters. All help much appreciated
Thank you all for your quick and very informative responses. Amazing! a 3-way tie for 'Best Answer' between mac44, retrocop and michaelmph. Appreicated.