Strange Adventures Vol. 1 (1950-1973) #217

Plot

An Earth archaeologist is caught by a "zeta-beam" and teleported to Rann near Alpha Centauri. He meets Alanna and Sardath. Alien invaders called The Eternals attack the planet. Adam and Alanna journey to the Brigadoon-like city of Samakand to locate a life-metal called "vitatron". Adam tricks the aliens so they're stuck in Samakand. Then he fades away, back to Earth! And waits for the next zeta-beam...