Ian Gillan

If there were a ranking of the most underrated artists in history, he would undoubtedly come in first. I fell in love with him through Made in Japan in 1972 and I haven't been able to prefer anyone else since. The only ones who can challenge his title of best singer and performer are Freddie and Amy, and we're talking about aliens from distant planets. Everyone else, as much as they are legends in their own right, can only come up to Ian's knees.