¡Ultimátum! (Alan Star)

"¡Ultimátum!" by Alan Star This Spanish-language pulp serial, published by Ediciones Toray in 1961, opens with a murder mystery. An elderly caretaker at the Parisian Biological Institute discovers Professor George Faust stabbed through the chest at his microscope after midnight. The professor had recently transferred from microbiological research to radiation studies at another institute, working six months with a German colleague named Krause before apparently abandoning the project. Agent Milo March of the SIP is dispatched to investigate. Callowan, his superior, notes Faust lived a quiet, solitary life with no apparent enemies, though his mysterious research shift and work with Krause warrant scrutiny. March is tasked with interviewing Faust's twenty-year-old daughter Juliette and interrogating Krause directly. The narrative follows March's arrival at Faust's modern home outside Paris, describing both the house's careful upkeep and March's physical presence as he approaches to question the bereaved daughter.