Graham Patrick Martin, Mary McDonnell Graham Patrick Martin, Mary McDonnell

Major Crimes' third season will be a family affair.

Not only does the case in the premiere (Monday, 9/8c, TNT) involve two children who have gone missing with their father while everyone in Major Crimes points the finger at the mother, but it also sets up a season that explores what "family" truly means.

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And how will Rusty's "family" at the precinct receive the news? "In 1973 I came out to my friends," Duff says. "The process of living your life as a gay person has changed enormously, but the process of coming out hasn't changed very much at all. It's more a problem for Rusty than it is for other people. It's saying, 'I'm really different from you,' and when you say it out loud, it just makes it more true. I think it's very hard for him, but the reaction from the squad is different than what he expected."

And that ultimately reinforces Duff's theme for this season. "Expectations can ruin us, but without expectations we sometimes don't perform," Duff says. "It's about how to harness the power of expectation to do good. Expectation is a tricky thing, but it's part of what made humans king of the jungle. Our ability to anticipate and look into the future and to understand the possibilities that await us, that's what moves the human race. And yet it's also a bit of a struggle."

Major Crimes premieres Monday at 9/8c on TNT. For more on the premiere, watch the video below to see why the show is our editors' pick: