The CBS crime procedural Blue Bloods may have aired their final episode of the eighth season, but it also marked the acting debut of John F. Kennedy's only grandson, Jack Schlossberg.

The son of the former ambassador to Japan, Caroline Kennedy, Schlossberg appeared in a scene with Jamie (Will Estes) and Eddie (Vanessa Ray) as Officer Jack Hammer.

"I don't make the rules, I just pretend to enforce them," wrote the 25-year-old on Instagram. "Cash me tonight on season 8 finale of Blue Bloods my dream come true!! Best show in the entire world."

He commemorated the special occasion with a photo posing with his mother; scene partners Estes and Ray; and Blue Bloods executive producer Kevin Wade.

On Saturday, Schlossberg even recorded the episode with his smartphone as it aired live and proudly posted it for posterity, captioning it with, "A line fraught with tension."

Off the set, the actor doubles as a student attending Harvard Law School.

So far, his other television appearances include 60 Minutes, and Global Agenda. In May, he made an appearance on the Today Show and talked about his proud family heritage and navigating his way through life to make his own mark.

I'm inspired by my family's legacy of public service. It's something that I'm very proud of. But I'm still trying to make my own way and figure things out. So stay tuned — I don't know what I'm going to do.

Fans of the show welcomed his character in the crime drama's season finale.

So who does Schlossberg admire most in the entertainment industry? That would be none other than Dwayne Johnson. He gushed about being "the Rock's greatest fan" in a November interview with People.

He's just like the funniest, best guy. And what I really love about him is that he is the hardest worker… I identify with that because I think hard work is very, very important, and so I just think he's the man.

After the episode aired, people noticed Schlossberg's uncanny resemblance to his uncle.

Congratulations on your acting debut, Jack! Hopefully it'll be just a matter of time seeing you on the silver screen combating criminals alongside the Rock!

H/T - EW, Instagram, Eonline, Twitter