The series, based on a sequence of novels by Edgar Wallace including a 1905 novel titled The Four Just Men, presents the adventures of four men who first meet while Allied soldiers in Italy during the Second World War. The men later meet again, and decide to fight for justice and against tyranny, using money donated for the purpose by their late commanding officer. They operate from different countries: Jeff Ryder is a professor of law at Columbia University in New York City, Tim Collier is an American reporter based in Paris, Ben Manfred is a crusading independent MP who works from London, and Ricco Poccari is an Italian hotelier based in Rome. Their reputation as the "Four Just Men" is well known.