Research in progress...
This one came up on my radar as Endurion has submitted a solution and game fix for...
Secret Service
https://solutionarchive.com/game/id%2C6 ... rvice.html
A German language game, listed in the database under the author Heinz Joachim Eifert
Looking at the screen on GB64...
http://www.gb64.com/game.php?id=11170&d=18&h=0
I can see that it describes itself as a port of the Apple II adventure America's Agent by C. Frey.
The publisher on GB64 is listed as CW-Publikationen Verlags GmbH/RUN
with a reference for RUN 1984/12
We also have the similar looking game, America's Agent aka Amerika's Agent in the database...
https://solutionarchive.com/game/id%2C9 ... Agent.html
...attributed to G. Retz.
...for the Spectrum version...
https://spectrumcomputing.co.uk/entry/5 ... icas_Agent
Although GB64...
http://www.gb64.com/game.php?id=14263&d=18&h=0
...has the C64 version credited to Michael Bauer, for the C64 screenshot on that entry in the database
Another America's Agent is also listed on GB64...
http://www.gb64.com/game.php?id=28689&d=18&h=0
...in the screenshot as being written by Carsten Frey with that C64 version by M. Weck.
There is a partial listing in the forum on Atari Age... (c) 1987/1997... for TI99/4A
https://forums.atariage.com/topic/19598 ... nt=2493120
...attributed to Carsten Ziepke with permission apparently granted "Agent was a Apple II prg (c) 84 by C.Frey. Used with kind permission."
Carsten Frey had some Apple II listings in Homecomputer magazine...
Tut-En Amun Pyramid Builder - https://archive.org/details/home-comput ... 1/page/26/
...and Helicopter Attack, Missile Attack, Space Business etc.
Small ads mentions...
https://archive.org/details/Happy.Compu ... en+frey%22
https://archive.org/details/Happy.Compu ... en+frey%22
America's Agent / Secret Service
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