This teenager grew up to become the guiding vision behind some of rock's greatest concept albums. Do you recognize him?

Coming out of England's psychedelic scene, he and his bandmates were forced to change musical direction when an influential member left. The next 15 years saw him assume creative control of the group, with their defining works exploring the relationship between the individual and society at-large, to great critical and commercial success.

Since then he's often revisited one of his most famous works - even as he's feuded with its co-creators - and been an outspoken activist against war and global poverty. Think you know who we're talking about? Click here to find out if you're correct!

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