Robert Pensén, a correspondent for a Norwegian telegraph agency, came to Paris on an assignment to write several articles about the Louvre art gallery. Instead, he becomes an unexpected witness to a monstrous crime. In broad daylight, the courier of a Credit Bank is robbed and killed. The criminals escape in a large gray car, taking with them one hundred and twenty thousand francs.
As it later turns out, those desperate thugs didn’t stop there—and soon Paris was shaken by a series of bloody, senseless murders, brutal in their cruelty.