Like most actors who cut their teeth in theater, Henry Fonda did not like surprises, but his daughter Jane Fonda improvised their pivotal scene together in On Golden Pond.

“When I said, ‘I want to be your friend,’ I reached out and touched his arm,” Jane recalls. “I could see him seize up. I could see tears begin in his eyes.”

The scene might have been sentimental muck in less skilled hands, but the genuine emotion the real-life father and daughter brought to On Golden Pond helped make it the second-highest-grossing movie of 1981. Forty years later, this tearjerker about aging, family and love still speaks powerful truths.

“It’s a universal subject,” film expert Pierre Montiel exclusively tells Closer Weekly, on newsstands now.

Jane Fonda and Katharine Hepburn's Tense Relationship

It also brought two film icons together. Katharine Hepburn, who played Henry’s wife, had never met the actor before filming began on New Hampshire’s Squam Lake. But she gifted Henry a “lucky” hat once owned by Spencer Tracy, and he wore it throughout the film.

“They fell into each other’s arms,” director Mark Rydell recalls.

Katharine and Jane’s relationship was not as warm. “She didn’t like me very much,” says Jane, whom Katharine goaded into performing her character’s backflip into the lake. “It took me
a month of rehearsals, and she would hide in the bushes and watch me,” Jane says. “But when I finally did it, she praised me and said I’d taught her to respect me.”

For Jane, who had bought the rights to On Golden Pond so she could act alongside her often aloof father, it was all well worth it.

“I was able, in the movie, to say things to him that I wasn’t able to say [before],” she admits. “We had a resolution in the movie that we didn’t fully have in real life.”

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