YOU OWE IT to yourself not to miss the latest in the Gelli scandal. Some scandals are more interesting than others. This one is world class. Shadowy financier mysteriously disappears from high-security Swiss prison cell. Vanished prisoner was grand master of outlawed Masonic lodge in Italy. Far-right political connections. Traces of blood in empty cell. Was he kidnapped? Wow.

Wait, here's more. No, he wasn't kidnapped. A guard in the Swiss prison admits helping him escape and make his way to the French border. He was to have faced a hearing within a few days on an extradition request from Italy, where he is charged with fraud, extortion and involvement in terrorist activities. Outraged Italian politicians assert that this elegant escape proves that the secret lodge known as Propaganda-2 is still in operation and its tentacles are everywhere. Double wow.

The lodge was exposed in the spring of 1981 when Italian magistrates searched a building belonging to Mr. Gelli and found a list of nearly a thousand alleged members. It included two Cabinet ministers, several dozen politicians, and high officers of the armed forces and secret services. Mr. Gelli disappeared, evidently going into hiding in Latin America; he had lived previously in Argentina, where he had associated with Juan Peron and his supporters. The Italian government fell.

Mr. Gelli seems to have been using his connections to funnel enormous amounts of European money into Latin America--some of it possibly into neo-fascist politics there. The vehicle was the Banco Ambrosiano of Milan, whose chairman, Roberto Calvi, was found a year ago hanged under a London bridge--perhaps a suicide, perhaps not. The bank failed, revealing losses in the range of a billion dollars in inadequately secured loans to Latin American borrowers, some of them shells. The Vatican's bank, it then developed, had endorsed some of those loans. Mr. Gelli came into public view again last fall when he was arrested in a Geneva bank while trying to obtain the release from a numbered account of some $50 million that may have come from the Banco Ambrosiano.

The development of this case is an indicator, among many others, of the rising competence and independence of law enforcement in Italy. For several decades after Mussolini's fall, Italians--understandably--chose to keep their police divided, underpowered, and on a short leash. But in the 1970s terrorism and organized crime persuaded them that the tradition of weak enforcement was getting dangerous. The quality of police work began to change. When prosecutors and investigators keep doggedly pursuing a case that cuts as close to as many established interests as this one does, that's a very good sign. As for Mr. Gelli, the Italian, Swiss and French police hope to be seeing him soon.