Episode 74 of The Trigan Empire
Chase For A Traitor
aka Het verraad van Hipsos (Dutch title)
The Betrayal of Hipsos (Dutch title, translated)
Chase For A Traitor was originally published in 6 installments in issues 860 (8 July 1978) to 865 (12 August 1978) of Look and Learn magazine.
Installments
860 861 862 863 864 865
Links
Plot summary (Dutch)