If you only know the Dance to the Music of Time by the TV series or if this is the first novel in the series you have read, then you may well be rather confused. The TV series uses elements from chapter three in this novel but omits Jenkins' time with the Welsh regiment which forms the majority of the book. And, though it is set in 1939-1940, don't expect any military action.
Instead, we get a splendid evocation of pretty dull soldiering in Wales and Northern Ireland during the Phoney War - compare this with the first novel of Waugh's Sword Of Honour trilogy. Those experienced in office work and administration will recognise some of these scenes. Jenkins deals with a variety of characters; chiefly the hard working but vainglorious Captain Gwatkin, the up and coming Idwal Kedward and the inept Bithel, as well as the men from the ranks; competent CSM Cadwallader, the impish Corporal Gwylt and the unpleasant Sayce.
But there is a window in the civilian world when Jenkins visits his pregnant wife, and meets up with various members of the Tolland family, Dicky Umfraville, Buster, et al. And he learns more about his one time lover, Jean, from Jimmy Brent. A new character, Odo Stevens, appears and he will recur, unlike most of Jenkins' WW2 comrades. The closing few pages reintroduce us to the series' Nemesis and he's back with a vengeance.
Readers of the first six novels will enjoy this, but it has less value to new readers.