Following on close on the heels of the gothic and somewhat (in my opinion) patchy Stained Class album, Killing Machine is a huge leap forward in terms of modernity, both in a heavier, more contemporary, guitar sound and basic song construction (verse, chorus, verse, chorus, solo, bridge, chorus). The art of the punchy, choppy, urgent and modern Heavy Metal riff emerges in spades on this album and Rob's vocals take on a harder and rawer edge, befitting of the heavier music. Compared to Stained Class, the songs are notably shorter, simpler and significantly more 80's in style, a fact reflected in the iconic cover art and the change in band image to the uniform of the NWOBHM that followed this (Judas Priest patented) of leather and studs.
There are ever green real Priest classics on here, such as 'Delivering The Goods', 'Burning Up' and 'Hell Bent For Leather', which arguably are the metal blue print for later Priest classics - `Running Wild' is the grand father of `Jawbreaker', `Evil Fantasies' resurfaces as `Pain and Pleasure' and later as 'Love You To Death' and `Take on The World' morphs into `United' and 'Defenders of The Faith'.
No songs about aliens, saints, savages or heroes on Killing Machine - it's all contract killers, rocking out and running wild heavy metal. Possibly Priest's finest album.