Justin Timberlake at the U.K. premiere of “In Time.” (Facundo Arrizabalaga/AFP/Getty Images)

The actor/singer/heartthrob recapped the experience on his blog, writing, “I knew I would have an evening that I wouldn’t forget. ...What I didn’t know was how moved I would be by the whole experience.”

De Santis asked Timberlake to the ball via Youtube after a fellow Marine asked Mila Kunis, Timberlake’s “Friends With Benefits” co-star, to be his date. Kunis accepted and will attend a ball in North Carolina on Nov. 18.

Timberlake said he spent the night laughing with De Santis’s friends a doing a little dancing. He described the Marines as “cool, un-affected, and real.”

But there was a more serious side to the evening, as well. Timberlake said he was “truly moved” by a video of Marines talking about their firsthand experiences in conflicts that played during the ceremony.

It was a surreal moment to be in that room with so many of our great Marines who have such a different type of connection to those stories.One that we who don't serve will NEVER understand. It was familial. It was like they were listening to their own blood brothers. I glanced around the room at young men and women, spouses and soldiers... At kids way beyond their years, really... All so deeply entwined. Not just by battle, even though we who have never endured anything remotely close to those experiences and have NO position to comment on... But, by having such life changing experiences through them and to not ever waver in their love and respect for our homeland. That's what I saw. A faith in us that has been tested time and time again. And, through it all, NEVER a drop of doubt.

Timberlake called all members of the armed forces his heroes: “Nothing makes me feel more honor and pride than when I get to meet one of you. Last night changed my life and I will never forget it.”

He also thanked De Santis, who he called “humble and honest,” for the invitation and “for being my hero.”

View Photo Gallery: The singer and actor has transitioned from boy band member to an acting career with frequent appearances on “SNL” and major productions such as “The Social Network.”