It was a caper involving Margot Fonteyn, Fidel Castro and John Profumo. John Wayne and Errol Flynn played cameo roles. So did Prince Philip. The result was a little-remembered Cold War contretemps from the Eisenhower era that might have slipped, unremarked upon ever again, into the mists of history.

But the other day Great Britain’s National Archives released 66 gripping pages of documents detailing how Dame Margot tried, at Castro’s bidding, to help overthrow the government of Panama in 1959. It was a opera bouffe version of a coup d’etat bungled by a prima ballerina — a woman in those pre-Beatles days universally considered Britain’s most recognizable and accomplished cultural personality.

And it was another reminder — unheeded, it might be added, by Gov. Arnold Schwarzenegger, the late Sen. George Murphy and, most tragically, by Charles Lindbergh — of the iron law that celebrity and politics don’t mix.

Fonteyn, who died 19 years ago, was married to Roberto Arias, at the time the Panamanian envoy to London and a member of a family that contributed four presidents of Panama, including his father.

From this distance, it is hard to know what was more disturbing, her involvement in the plot, which included a yacht, guns, a mountain hideaway and Cuban mercenaries, or the cavalier way — “charmingly light-hearted,” in the words of a British official who obviously was not amused — she attempted to dismiss the episode after being arrested.

But it was clear, at least to the mortified diplomats who had to clean up after the incident, that Fonteyn “seems quite genuinely to believe that the lot of the ordinary Panamanian would be greatly improved if the present government were to be replaced by her husband and his supporters, a point which I imagine is open to very considerable doubt,” according to a confidential memo written at the time by Sir F.R. Hoyer Millar, the permanent undersecretary in the British Foreign Office.

The British began to get suspicious days earlier when Dame Margot, who had enthusiastically accepted an invitation to a reception in Panama for Prince Philip, failed to turn up at the event. Before long, British diplomats were being roused from their beds to deal with what one of them described as “the incarceration of our prima ballerina assoluta” in a Panamanian prison’s “presidential suite,” where she was presented with fresh flowers for her dressing table, and to address questions about “the revolutionary activities of her husband.”

In prison, the ballerina discussed her activities with the diplomats in what Sir Ian Henderson, the British ambassador to Panama, described as “conspiratorial whispers which I discouraged in front of the police.”

The ambassador later described what he called “the holiday of Dame Margot” as a disaster. “She has almost complicated our relations with this little country, being regarded with hostility by some and with romantic sympathy by others,” he wrote. “Her conduct has been highly reprehensible and irresponsible to a degree. I sincerely hope that her friends and relations … will urge her to keep away from Panama for a very considerable time.”

But we’re not done yet. Shortly thereafter, Dame Margot visited Profumo and his wife in their home in London. Profumo, then minister of state for foreign affairs, said he had to “pinch myself several times during her visit to be sure I wasn’t dreaming the comic opera story which she unfolded.” (Profumo later would attract international attention when he resigned as secretary of state for war in 1963 after an affair with a call girl who also was having sex with a Soviet naval attache.)

During that visit with the Profumos, Fonteyn set forth the whole plot, which included gunrunning and soldiers of fortune and a complicated plan to collect rebels from various fishing boats. These rebels were to have worn white armbands so as to be readily identifiable, perhaps not the smartest technique ever conceived. When one of the rebels in stylish green jumpers was caught, he told authorities about a cache of machine guns and ammunition and an address book that contained the names of some of the combatants, along with John Wayne and Errol Flynn, who presumably were simply on her husband’s friends list.

In any case, Fonteyn assured Profumo that her husband had no intention of nationalizing the Panama Canal and probably didn’t want to become president himself. She said that this effort had been encouraged by Castro, but she bid Profumo to keep that confidential, creating a bit of a bind for British authorities. “We would normally have liked to pass this information on to the Americans,” he wrote, “but it is rather difficult to do so in view of Dame Margot’s request that everything she said should be treated as confidential.”

These documents, produced by typewriter and fountain pen, are a reminder of the Cold War tensions that preoccupied world powers and small nations for more than a generation. It was a time when no plan or plot was too peripheral to cause superpowers to take notice, not even the notion that a world-famous ballerina, whose most famous entanglement with the Soviet bloc would be her artistic partnership with Rudolf Nureyev, could try to overthrow a Central American government.

But it is also a reminder of the difficulty for celebrities to transfer their success or even their influence into the political world.

“Their skills and popularity are not transferable,” says Frank Mankiewicz, who was press secretary to Sens. Robert F. Kennedy and George S. McGovern and whose father, Herman Mankiewicz, was among the most famous Hollywood screenwriters of the 1930s and 1940s. “We don’t think of them as politicians and there is a reason for that. People in show business think they know more about politics than they do. They think they know more about everything. If you’re worshipped and adored by millions that can do that to you.” (The great exception: Ronald Reagan.)

In Dame Margot’s case, she also thought that an indiscretion that became an international incident could be wiped away with a beguiling smile, a laugh and a wave of the hand.

For their part, the British also dearly wished this episode to disappear. “It is in fact our hope that this whole Panamanian excitement will die down fairly soon,” Millar wrote, “and that in the meantime — and indeed in the future — Dame Margot will keep out of the revolutionary business.”

— David Shribman is executive editor of the Pittsburgh Post-Gazette.