Kazuhiko Tatemoto, (1940–2011) received his B.Sc. from Waseda University, Tokyo. After working in a company in New York, USA, he toured Europe and fall in love with Sweden. From 1967–1982 he became a Research Assistant in the Department of Biochemistry, Karolinska Institute where he met extraordinary scientists. He joined the laboratory of Hugo Theorell, who had been awarded the Nobel Prize in 1955 "for his discoveries concerning the nature and mode of action of oxidation enzymes" working on alcohol dehydrogenase. In 1977 he joined the laboratory of the warm, brilliant and generous scientist Viktor Mutt, successor of Erik Jorpes as professor of medical biochemistry. Establishing a novel chemical determination of polypeptide hormones they made a fundamental brake through in the discovery of many gut-brain peptides (Tatemoto K & Mutt V. Proc Natl Acad Sci U S A 1978) leading to centennial discoveries like PYY, NPY & galanin. He defended his thesis 4 years later and moved in 1985 to Stanford University School of Medicine, California, USA, Department of Psychiatry and Behavioral Sciences where he and his colleagues isolated pancreastatin. In 1991 he moved back to Japan and became a Professor at the Institute of Endocrinology, Gunma University, Maebashi. There, he used a reversed pharmacology approach isolating novel ligands to orphan receptors which yielded in the discovery of apelin. He retired in 2006 and became a visiting professor first at the AI Virtanen Institute at the University of Eastern Finland the year later and in 2008 at the Institute of Biomedicine, Oulu University to pursue and spread his ideas. He continued the supreme legacy of his mentor Viktor Mutt, providing us with novel signal substances in multiorgan cross talk.