The blurb on the back:

'You didn't kill him did you, Ron?' he said piteously. 'He's all right, isn't he?'
Dimly - very dimly - Les realized that he was caught up in something big which he could not control. He was no longer a free agent....
Whether he liked it or not, they'd have to hang together - and the phrase sent a wave of terror through him.
John Bingham, one of the foremost 'straight' novelists of our day, tells the story of Les, a cosh-boy, who was fundamentally harmless, but weak and impressionable - a story which moves us to pity and horror.

opening lines:
Leslie Marshall, aged 19, of 354 Dale Road, Streatham, London, lay in bed. Mostly he gazed up at the ceiling but sometimes he turned on his side, and then he could see the moonlight bleaching the pink blossom of the hawthorn tree in the garden of the house opposite.

This is vital historical stuff. Published in 1954, just before rock & roll broke into Britain, it's a fantastic portrait of a nation's youth waiting for the kick start it needed:

He thought again of Monday night at the Arcady Dance Hall, and it seemed to him in retrospect that after each dance Hester had been more and more reluctant to leave the floor. She'd lingered chatting to him while the others drifted from the floor; the young sleek men in gaberdine draped suits, and pseudo-Edwardian suits, and wine-coloured jackets and beige trousers, and startling ties; the occasional soldier, the odd Negro here and there, and the girls in their cheap dresses and their trinkets. (p.6)

It's all there: the style, the surplus money, the attitudes, the need to dance. Even the obsession with American culture is present, but as a nation waited for Bill Haley to unleash Hell from the other side of the Atlantic, the focus is instead on Hollywood cool. Our 19-year-old hero Leslie Marshall is 'film-ridden and phoney': a Fleet Street office boy with attitudes and pretensions way above his station, he gets dragged into a criminal career as a result of hanging around dance-halls and mixing with the wrong sort. In other words, he's lower-middle-class and he spends too long with working class types, who lead him astray. This is, in short, a Morrissey song waiting to happen.

John Bingham - otherwise known as Baron Clanmorris - was the author of a decent-sized shelf-load of books, including Five Roundabouts to Heaven, I Love, I Kill, Night's Black Agent and Murder Plan Six. I haven't read any others, but I suspect they'd be worth having a look at.