They talked about jazz-rock for years, but it took John McLaughlin to finally achieve something like it – and simultaneously make it redundant – with his post-Miles ensemble Mahavishnu Orchestra. The music on Inner Mounting Flame is a realisation of Zappa’s experimental probing into new forms of progressive rock on the earlier Hot Rats, with McLaughlin taking it to the viable limit on brain-curdling tracks like “The Noonward Race”.