Michael Weatherly on moving on from "NCIS"

In 2003, Michael Weatherly debuted as special agent Tony DiNozzo in the premiere of the number one drama, "NCIS." Thirteen seasons and over 300 episodes later, Weatherly has come "full circle," as he makes his final appearance on Tuesday's season finale.

"I feel very whole, complete and excited... it's a huge accomplishment, there's a sense of graduating and that's deeply satisfying," Weatherly told "CBS This Morning" Tuesday.

When the actor first began the show, he was also playing Robert Wagner in a 2004 mini-series, "The Mystery of Natalie Wood," directed by Peter Bogdanovich. Then six years ago, Wagner was hired in season seven of "NCIS" to play Weatherly's father.

"And last week, I went to the wrap party with Wagner and as I was getting into the car, Peter Bogdanovich walks by and goes, 'Hey,'" Weatherly said, recalling the "full-circle" moment. "And it was one of those moments where you thought, 'Oh, the synchronicity has happened.'"

Long-time co-star Pauley Perrette sent Weatherly a warm farewell message, saying, "We've been partners in crime in this thing for 14 years. My heart belongs to you so much, my brother, I love you. I never want to do anything without you and you're just going to be so missed and so loved."

Teary-eyed, Weatherly said that he had built a "retaining wall" around his emotions that he anticipated would come down after the final episode airs Tuesday evening.

Now, Weatherly graduates onto a new CBS show, "Bull," playing a Dr. Jason Bull, inspired by daytime talk show host Dr. Phil during his early days, running a prolific trial consulting service. Written by McGraw and Paul Attanasio - writer of "House" - and produced by Steven Spielberg, Weatherly called it a "real heavy-hitter show."

"But the great thing was when the client said, 'What about innocent until proven guilty?' And Bull says, 'Innocent until proven guilty is like two all-beef patties, special sauce, lettuce, cheese, pickles, onions on a sesame seed bun,'" Weatherly recited a line from the show. "'It's the ad, it's the slogan, but it's not the truth.'"

But before that, you can catch the season finale of "NCIS" Tuesday at 8 p.m./7 p.m. Central.