Mark Harmon: TV's Most Popular Man

Harmon's father, Tom, won the Heisman Trophy in 1940 and worked as a sports broadcaster. For a time it looked as if Mark, who was raised in Southern California and played quarterback at UCLA in the early 1970s, would follow in his dad's path. But fate had other plans.

One of Harmon's first acting gigs was a cruise on The Love Boat with fellow guest star Lisa Hartman. After a run of minor TV roles, he said: "The guys I played didn't have names." 

This Alan J. Pakula-directed Western marked Harmon's movie debut. It was a small part — he played a rancher — but his Hollywood career was off to a gallop.

Harmon headed back to TV for a starring role in this 1981 prime-time soap, opposite Morgan Fairchild (pictured). Flamingo Road lasted just two seasons, but it gave a nice boost to Harmon's visibility, as did a brief, high-profile romance with actress Heather Locklear.

Harmon (pictured with Nancy Stafford) spent three seasons on the NBC hospital drama St. Elsewhere, starring as ladies' man Dr. Robert Caldwell. He left the show with his profile still on the rise, thanks to a landmark story arc as one of the first prime-time TV characters to contract AIDS.

"Charmin' Harmon," he was called in a story proclaiming Mark as People magazine's Sexiest Man Alive in 1986. At 34, he was still single, but sounded ready to settle down. "When I marry, I want it to be everything this town says it can't be. I'm not into catting around."

Harmon proved that he could have some fun with his newly bestowed title in a memorable Saturday Night Live skit during a 1987 hosting gig. In the sketch, Harmon narrowly beat out a disappointed F. Murray Abraham (Jon Lovitz) as the planet's sexiest man.

Even sexiest men eventually settle down, and Harmon's words to People about marriage proved prescient. In 1986, he began dating Pam Dawber, and the next year he married the actress, most famous for her starring role on TV's Mork and Mindy.

Even though it was a goofy summer comedy, in which Harmon starred as a carefree summer-session teacher, it was a good career move. Directed by Carl Reiner, it grossed nearly $30 million — and it's still Harmon's biggest box office hit.

As the summer of 1988 began, The Presidio, which starred a red-hot Harmon, rising star Meg Ryan and a rejuvenated Sean Connery, looked to be one of the season's biggest hits. But the San Francisco-set military crime drama underperformed and underwhelmed the critics. "Harmon seems to lack charisma," wrote Roger Ebert.

Harmon returned to the small screen and starred with Marlee Matlin in this legal drama, playing an investigator for Matlin's Chicago assistant D.A. The show lasted two seasons and stabilized his career, earning him two Golden Globe nominations as Best Actor in a Drama.

By 1996, he and Pam were raising two sons. He joined the doctor drama Chicago Hope. He was saving people in real life too, making headlines by extracting two kids from a burning vehicle. "The youths owe their lives to the actions of Mr. Harmon," an LAFD spokesman said.

Twenty-five years on, Harmon and Dawber's marriage is still going strong. They are pictured here with Harmon's mom, actress Elyse Knox, who died in 2012, and elder son Sean, who has portrayed a younger version of his dad's NCIS character on several episodes.

A four-episode arc in 2002 on Aaron Sorkin's Oval Office drama paid off nicely: Harmon garnered his second Emmy nomination (as Best Guest Actor) and reestablished his small-screen cred. He's pictured with Allison Janney.

In 2003, Mark found his landmark role as Special Agent Leroy Jethro Gibbs on the long-running CBS hit, which remains TV's most-watched scripted show in its 10th season. Last year, at 60, he was named TV's most popular personality in a Harris Interactive poll for the second consecutive year.