Tom Selleck wants to get one thing straight: “It’s not like I’m retiring or anything.” After more than five decades in the entertainment industry, the 79-year-old Emmy-winning actor has written a memoir. For the first time, Tom opens up about his career, spanning from his early days in the Fox New Talent program to his breakout roll on Magnum to his current turn on Blue Bloods.

In a brand-new interview, Tom sat down with Country Living to talk about You Never Know, available now.

As Tom explains, he’s “pretty private,” and convincing him to write a memoir wasn’t easy. “I hesitated for a long time because I didn’t, you know, screw up and end up going to prison and have to start a new career,” he says. “I just said, ‘What am I gonna write about?’”

“I knew I wasn’t going to do a get-even book or a tell-all book or a political book,” Tom explains. “So I just had to think about it because my publicist is a dear friend, and she just kept on me. It took about four years. I prefer to be computer illiterate, so I wrote with a pen and yellow pad.”

It turns out, he had plenty to write about. “Then I got into it and had some ideas about what I would talk about. As much as I wanted to talk to the reader, I also wanted to talk to young actors and people in the business to let them understand.” He drops in some highlighter-worthy life lessons along the way, like: “You have to choose to be offended.”

Tom opted for a conversational style, discussing his friendship with Sam Elliott (formed while they worked together in the Fox New Talent program), his time in Hawaii filming Magnum (and his now-iconic costumes), his near-miss on Raiders of the Lost Ark, attending the Academy Awards with Carol Burnett, and even dancing with Princess Diana at the White House.

On His 36-Year Marriage
Most of his memoir focuses on his career. In fact, in You Never Know, he doesn’t mince words about keeping his private life private. “When I undertook this project, I made a commitment to share my private, personal emotions and feelings…primarily about my work,” he says. But he does spend a poignant chapter reflecting on his secret wedding to his wife of 36 years, Jillie Mack.