Stéphane Brangier, who signs with Siro, began his career as an illustrator for the press, children's books and the advertising field. He made his comics debut in 1992 with the series 'Master Volume', of which he wrote and drew two books at the publishing house Zenda. He then teamed up with writer Didier Convard and began the 'Polka' series at Dargaud.
He took over 'Aquablue' from Tota at Delcourt, drawing two books between 2004 and 2006. Siro worked with Eric Stalner on the artwork of the final two installments of the series 'La Croix de Cazenac' in 2007 and 2008. He then teamed up with Bollée to create the science fiction serial 'Speedway' at Dargaud.