Ben Affleck has the sweetest story about "Star Wars" actor Adam Driver.

Appearing on Jimmy Kimmel Live on Tuesday, the "Batman v. Superman" actor recalled how Driver sent special gits to his 8-year-old son Samuel on his birthday.

Knowing that his son is a "Star Wars" fan, Affleck asked his co-star Adam Driver to record a video of him as Kylo Ren as he greets the birthday boy a Happy Birthday. Driver happily obliged.

Kylo Ren: The Real Hero

In addition to the video, the "Justice League" star brought presents in advance for his son's birthday party while he was out of the country shooting a movie with Driver.

After rushing back to Los Angeles to head directly to his son's party, Affleck found out that the presents he ordered did not arrive.

It meant he was going to show up at his son's birthday party with no gift, explaining that there was as a "sinking, awful feeling" not having something to give to his loved one.

When Driver found out what happened, he saved Ben Affleck by sending him "Star Wars" themed toys and even a signed photograph of Kylo Ren.

Affleck recalled that at the last minute, Driver reached out to Affleck's assistant so he could send him the presents.

The dad went on to describe how the events unfolded when explaining to his son why his gifts did not get there on time.

He reportedly told Samuel, "But I did get a present from somebody who really wanted to make sure you got a gift,' and he was like, 'Who?' and I said, 'Kylo Ren.'"

Ben Affleck then played the video of Driver as Kylo Ren and detailed the exact moment to be "an incredibly moving and powerful moment" while holding back tears.

Reflecting on Driver's generosity, he concluded, "Adam made me a hero to my kid and I will never, ever, ever forget it."

Affleck added that it is a really good lesson in doing "small gestures of kindness."

Adam Driver, Ben Affleck Co-Star in a Movie

Ben Affleck and Adam Driver were recently spotted on the set of their latest movie "The Last Duel" in Sarlat, France. The movie is directed by Ridley Scott but the film is based on Eric Jagger's 2004 nonfiction book, "The Latest Duel: A True Story of Trial by Combat in Medieval France."

The script comes from Nicole Holofcener as well as Affleck and Matt Damon, marking the first time the latter two have shared a writing credit ever since winning the 1998 movie "Good Will Hunting."

The film tells the story of Jean de Carrouges (Damon) and Jacques Le Gris (Driver) who are based on two real-life 14th century knights.

After Jean returns from war, he accuses Jacques of raping his wife and turns to King Charles VI for help.

King Charles VI, in turn, ordered the two former friends to fight to the death. If Jean loses, not only will he die, but his wife will also be burned to death.

Ben Affleck plays a supporting role in the film. "The Last Duel" will premiere in late 2020 or early 2021.

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