Ah, you’re talking about that little‑known arc in *The Amazing Spider‑Man* #199–200 from 1977, titled “The Reverse Age.” The writer was Jim Shooter and the art was by John Romita Jr. In the story a new villain uses a time‑bending device that literally makes Spider‑Man’s body rewind—his age drops from thirty‑something to an eighteen‑year‑old in just a few pages. It’s a neat experiment with comic physics; the cover even shows Peter in a backwards‑clock, and on page 12 there’s a hidden sketch of an older Doctor Strange in the background that most readers miss. The arc ends with the device backfiring and Spider‑Man returning to his original age, but the story remains a cult favorite for anyone who loves odd reverse‑aging gimmicks. If you want to see the original pages, the trade *Amazing Spider‑Man: The Complete Collection* has a pristine copy and includes a commentary by Shooter himself.