To me, it's one of those all-time great majestic Blackmore riffs (though it was never a real hit), in a class with Smoke on Water, Burn and Knocking On Your Back Door, that Ritchie recipe of playing a riff in those slightly nasty sounding parallel fourths on the D and G string. And following the riff in G minor, the verse of the song doesn't start on a G minor chord (as most DP and Rainbow songs would) as the root (I), but moves mostly in half-bars (also unusual for Deep Purple or Rainbow) as follows:
VII - IV - I - VI - IV - VII
I - VII - IV - VI - IV - I
followed by the bridge
V - III - V - II
III - IV - III - I
VI - VII
before hitting the G minor root note riff again.
That's not exactly PROG, but for a Purple/Rainbow chord structure pretty nifty. A lot of Blackmore numbers are four or five chords that move mostly in full or double bars, here he was trying something different here. (Deep Purple/Rainbow both weren't exactly 10cc as frequent chord changes go.)
If Blackmore hadn't already had a wandering eye for a way out from Purple, MOTSM should have been on Stormbringer. It would have been interesting to have heard what Coverdale, Hughes, Lord and Paice would have made of it. But in the Stormbringer sessions, Ritchie was already hoarding for his solo album (= the Rainbow debut) which he immediately recorded afterwards in Munich with DP-opener Elf (sans their lead guitarist Steve Edwards of course) as his backing band.
Your fellow-Holländers don't do a half-bad job with it, I've heard that song played and sung worse so often.
(Let's face it: UDO's not very agile voice has issues covering all those chord changes.)
I like how the Dutch singer sounds like a cross between Dio and Coverdale, that gives it a Purple feel. Compliments!
