Fantastic Four #155 Feb 1975
"Battle Royal!" Guest-starring the Silver Surfer
The Fantastic Four's afternoon walk through Central Park is interrupted...first, by a gang of thugs,
and then by the Silver Surfer! Why is the former herald of Galactus attacking the FF?

The surfer reveals in a surprising development that he's located

his beloved Shalla Bal in a castle in the Balkans! Two major problems though:

the castle is located in Latveria...and the castle is occupied by Doctor Doom!

Script by Len Wein. Art by Rich Buckler (layouts) and Joe Sinnott (finishes).