The actors starred in Wild Angels together, which was Ladd's first film, and The Last Full Measure, which turned out to be Fonda's final film
Shortly after news broke that Fonda died on Friday, Ladd, 83, paid tribute to her longtime friend and costar, who she had worked with and come to personally know for more than five decades.
As she looked back on their friendship, Ladd noted how she starred alongside Fonda in her first film, Wild Angels in 1966, and serendipitously, had an opportunity to work with him again on The Last Full Measure, the final film before his death.
“Peter was a friend, a wonderful actor, and a great humanitarian,” she tells PEOPLE. “He rang a bell for culture. He will indeed be missed.”
“We recently had the privilege of working in a new film together to be released this year that will not only entertain, but lift up humanity, The Last Full Measure,” Ladd continues. “I remember when we were filming Wild Angels, my very first film, we were practically children back then.”
The actress went on to recall a specific memory from filming the 1966 drama-crime that stuck with her through all these years.
“It was a foggy night and some bikers came up the mountain and threatened to tie Peter and another crew member to a generator,” she says. “Peter and Bruce Dern protected us and led us all to safety. His courage always shined through like that.”
In an exclusive statement to PEOPLE, Dern, 83, also praised his former costar. “Peter Fonda always dared to dream. His incredible patience will be missed — he loved to push the envelope. He was quite simply a ‘true seeker.'”
Wild Angels, which also starred Nancy Sinatra, followed a San Pedro motorcycle gang called the “Angels” as they stirred up trouble in Coachella Valley after their buddy’s bike gets stolen.
Fonda portrayed the leader of the gang, “Heavenly Blues,” while Dern was his best friend “Loser” and Sinatra and Ladd played their love interests.
The Fonda family confirmed the sad news about Peter’s passing in an exclusive statement to PEOPLE on Friday and said that the two-time Oscar-nominated star died after suffering respiratory failure due to lung cancer.
“It is with deep sorrow that we share the news that Peter Fonda has passed away,” the family said. “[Peter] passed away peacefully on Friday morning, August 16 at 11:05 a.m. at his home in Los Angeles surrounded by family.”
“In one of the saddest moments of our lives, we are not able to find the appropriate words to express the pain in our hearts. As we grieve, we ask that you respect our privacy,” they continued.
“And, while we mourn the loss of this sweet and gracious man, we also wish for all to celebrate his indomitable spirit and love of life,” the family finished. “In honor of Peter, please raise a glass to freedom.”
Peter was best known for playing the role of Wyatt in 1969’s Easy Rider, which he also produced and co-scripted. For his work on the project, Peter earned an Academy Award nomination for Best Original Screenplay.
Aside from Easy Rider and Wild Angels, the actor starred in Ulee’s Gold, The Hired Hand, and The Trip.
Throughout his lifetime, he also directed a number of projects and earned himself several accolades along the way, including four Golden Globe nominations (two of which he won), one Emmy nomination and another Oscar nomination for Ulee’s Gold.
More recently, Peter was featured on television series, including CSI: NY, Hawaii Five-O, The Blacklist, and Milo Murphy’s Law.
At the time of his death, he was in pre-production for a movie called Skate God, expected to release in 2020, according to his IMDb. The last film he acted in alongside Ladd, The Last Full Measure, is expected to be released later this year.