German media say that deceased actor Horst Tappert, best known for playing dapper TV sleuth Stefan Derrick, served in a feared Nazi SS unit.
Reports say that newly discovered historical documents show Tappert was in an elite SS armored infantry regiment which also fought on the eastern front.
The SS is known to have committed atrocities during World War II but it is unclear whether Tappert was involved.
"Derrick," produced between 1974 and 1998, was one of the most widely syndicated German TV shows, broadcast in over 100 countries including China.
Tappert died in 2008. Germany's ZDF television which produced "Derrick" didn't immediately respond to requests for comment.
Dutch public broadcaster NOS reported Saturday that TV station MAX was pulling reruns of "Derrick" from its schedule over the SS revelation.