I probably caught some of this series in the early days of Channel 4 which started a trend of repeating vintage shows.
Based on characters created by Edgar Wallace. The television series produced by ITC had a multinational cast. Jack Hawkins as Ben Manfred a British Member of Parliament with an interest in human rights. Richard Conte as Jeff Ryder, an American professor of law. Dan Dailey as Tim Collier, an American foreign correspondent based in Paris. Vittorio De Sicca as Ricco Poccari, an owner of a luxury hotel in Rome.
The first episode is an origins story. The four men arrive to remember their late commanding officer Colonel Cyril Bacon. He has died but has left them an important message.
There are flashbacks to a dangerous mission in Italy during 1943. Where the men met for the first time. A not so harmonious first meeting for some of them. How they were aided by a young Italian boy working for the local resistance and who got injured.
The message from the Colonel is a call to arms to fight injustice and tyranny. The first episode has all the four main actors together, a feat that would only be repeated in one other episode. Interestingly the sentiments of the Colonel are a direct consequence of the atrocities caused by the Nazis in world war 2. Also fears of what was happening in the Soviet Union.
Nowadays the late Colonel who it turns out adopted the injured boy would be locked up along with the Four Just Men for being a do gooder. You can't have people standing up for human rights.
The rest of the series would feature would concentrate on one of the just men. That way they could film concurrent episodes.