Alan Whitmore, a young American researcher, goes to Budapest to visit Professor Roth, with whom he collaborated on a secret project called "Intextus" while a mysterious killer in on the loose...

Alan Whitmore, a young American researcher, goes to Budapest to visit Professor Roth, with whom he collaborated on a secret project called "Intextus". Once he arrives in the Hungarian capital, Alan finds Roth who hands him a black book which includes information of the utmost importance.