In their forty-three year (!) recording career, it isn’t unfair to say UK rock stalwarts Def Leppard are known for a pretty steady formula and approach of, in the main, pristine, polished hard rock songs, centred in an eighties sheen. Most of us could recognise a Def Leppard-style song without too much difficulty, and they aren’t (a few deviations – RetroActive, Slang, Taylor Swift, and Ghostly interactions – aside) known for their musical risk-taking or surprises.