Action Comics 340, Aug 1966 comics.org
Shooter's Credit: writer
Story Title: Power of the Parasite
Publisher: DC
Reading Status: required
Script: Jim Shooter
Pencils: Al Plastino
Inks: Al Plastino
Colors: unknown
Letters: unknown
Synopsis: Jensen is blasted with radioactive waves and transformed into Parasite. Parasite discovers Superman's secret identity and threatens to expose him unless Superman fights.
Characters: Superman, Parasite, Perry White, Lois Lane
Places: Daily Planet, Metropolis
Origin of: Parasite
Death of: Parasite
Cliffhanger: During the fight, Parasite has absorbed all of Superman's physical energy and peers into his eyes to drain his mental energy.
Conclusion: Parasite body was unable to contain Superman's powerful mental energies and was destroyed.
Notes: Shooter's writing credit obtained from reprint in Best of DC Blue Ribbon Digest 10, March 1981. Parasite's death possibly retconned.