Mr. Hyde

Calvin Zabo, a ruthless chemist obsessed with Robert Louis Stevenson's classic tale, developed a formula that transformed him into the brutish, super-strong criminal Mr. Hyde — his dark alter ego — and soon clashed with Thor after debuting in 1963.

Few villains carry the weight of classic literature and Marvel mayhem quite like Mr. Hyde, who crashed onto the Silver Age scene in Journey into Mystery #111 in 1964, conjured by the legendary duo of Stan Lee and Jack Kirby. Over six decades of continuous troublemaking — from the pages of Avengers to Captain America to Daredevil — he's proven himself one of Marvel's most enduringly dangerous presences, the kind of threat that keeps even the heaviest hitters on their toes. His catalog includes two key collector issues, and the company he keeps tells the whole story: this is a character who has gone toe-to-toe with Thor, Spider-Man, and Captain America across generations of Marvel storytelling. If you're building a serious understanding of Marvel's rogues' gallery, Mr. Hyde is essential reading.