THE YEAR WAS
"Captain Marvel vs Spy Smasher" - Part 1
Written by Bill Parker(writer), Pete Costanza(artist)
From Whiz Comics #15 - When Eve is captured by Grosso under the direction of the Mask, Spy Smasher rushes to save her but is instead captured and put under the control of the Mask via his Brainograph. Now evil, Spy Smasher kills the Mask but Captain Marvel shows up to try to capture him.
Here are the pages I have of it.