Dan and Kate attempt to expose a phony spiritualist who has been exerting undue influence over a powerful senator.

The Westins must prevent a suspected spy from being assassinated before they find out how she has been stealing documents, and to whom she has been selling them.

At a scientific conference in Stockholm, Dan must determine whether a former defector is sincere in his request for help to escape back to the U.S.

The Westins conspire to help Walter's Aunt Margaret replace the money she "borrowed", from the bank where she is employed, to support her gambling habit.

When one of the corpration's co-owners, Caroline Klae, is threatened and then kidnapped after she refuses protection, one of the other siblings makes a grab for power.

An escaped mental patient holds Director Carlson hostage and demands that he be given the secret of Dan Westin's invisibility.