The Swiss Conspiracy - Martin Schuller, Spy Catcher

Dangerous and mysterious events are afoot in a peace-loving land... Someone is killing Swiss colonels, and painting a hammer and sickle at the scene. When Dr. Fritz Rubenstein, a physicist in Zurich, is gunned down in his office, the only clue is a letter in his trash requesting assistance for the French Resistance. Swiss Intelligence is new, underfunded, and understaffed, and they ask the U. S. government for help. Martin Schuller is sent to Switzerland to go undercover to find the killers, and what they're after. As war rages all around, Switzerland is an island of serenity.
But Switzerland in the fall of 1941 is not all it appears. Delving beneath the serene appearance, Martin finds a secretive world of right-wing organizations, idealistic student activists, banks full of Nazi gold, and competing foreign agents. With the help of Franz Lemiel, a world-wise artist and activist, and Jason Bachman, an eager young American diplomat, Martin discovers a conspiracy to bring down the Swiss government in one dramatic event.
Can he stop the conspirators from carrying out their attack, and changing the entire course of the war? Book Three in the Martin Schuller Spy Catcher series brings new dangers, and forces Martin to blur the lines between spy and spy catcher. It reintroduces a character from Gray Paree, a companion novel to this series.  Content warning: This book contains a dark sequence involving torture in a Gestapo dungeon, including sexual assault.
This is realistically portrayed, and may be traumatic for certain readers.