Superman's Pal, Jimmy Olsen #101

The cover of this April 1967 issue lays out a wonderfully wild premise: Jimmy Olsen — in his purple-and-yellow costume — has traveled back in time to Krypton and is holding a tiny, caped baby Kal-El, while a growling Krypto lunges at his heels and the boy's parents look on with alarm from a futuristic doorway. The tagline "Can Jimmy Change History?" perfectly captures the gleeful Silver Age audacity of the story inside, "Olsen's Time-Trip to Save Krypton!" Cover pencils by Curt Swan and inks by George Klein give the scene that clean, expressive energy that defined DC's storytelling style of the era.