ABC only made the first hour of tonight’s two-hour premiere of “Grey’s Anatomy” available for review and asked critics not to reveal important plot details.



But I can reveal one thing about the episode, titled “Good Mourning:”



Sight unseen, the second hour, “Goodbye,” has to be more intriguing than the sappy first hour that deals with last spring’s season-ending life-threatening situations involving George O’Malley (T. R. Knight) and Izzy Stevens (Katherine Heigl).



Of course, in this Twitter-gossip world that we now live in, few plot secrets can be kept from the entertainment magazines determined to take the fun out of shows by revealing surprises.



By now, just about every “Grey’s” fan who can read knows who is going to live, who is going to live, who is going to die and who is taking off several weeks to deal with a real-life pregnancy or to make a movie.



Go Google if you really want to know what is happening in the lives of Knight, Heigl and Ellen Pompeo (Meredith).



As far as what’s happening starting at 9 tonight on “Grey’s,” the maudlin nature of the first hour is broken only by some inappropriate humor, a new plot about hospital politics and finances and a gruesome medical case involving a foreign visitor to Seattle that deals with quality of life issues.



I suppose the sentimentality in the opening hour was inevitable in an episode that should have been titled “Everybody Loves George” and may even please some faithful viewers who need a good cry over a beloved fictional character — and a few laughs.



My favorite moment arrives when one of George’s colleagues inappropriately asked the question that many viewers were asking over the years as the nerdy, average-looking guy with an oversized heart scored with so many pretty women. Regular viewers can predict the question and who asks it.



Writer-creator Shonda Rhimes seems to be uncharacteristically winking at the audience in that scene. Rhimes and ABC Entertainment President Stephen McPherson have said the show is “evolving” or in “transition.” In other words, in its sixth season it needs to reinvent itself like NBC’s long-running “ER” did by adding new characters.



It could take awhile for some new regular characters to show up. But one thing is clear from the first hour — they can’t arrive too soon.



Dexter as Daddy



Dexter Morgan, family man? Hank Moody, college professor?



Those are the odd concepts in two of Showtime’s more popular series. “Dexter,” in which Michael C. Hall plays a blood-splatter analyst and serial killer out for justice, returns for a fourth season at 9 p. m. Sunday. “Californication,” in which David Duchovny plays a novelist and serial philanderer, returns for a third season at 10 p. m. Sunday.



The compelling opener of “Dexter,” “Living the Dream,” suggests that Dexter Morgan (Hall) will be vulnerable to making mistakes now that he’s a very tired daddy. And since he solves crimes for Miami Metro Homicide and commits them, he is vulnerable on two fronts.



The opener introduces John Lithgow as the latest serial killer, Arthur Mitchell, or “The Trinity Killer.” We see a lot more of Lithgow’s body Sunday than many of us might want, but we don’t hear much out of his mouth.



The case brings back Special FBI Agent Frank Lundy (Keith Carradine), who has been following Trinity for decades. Meanwhile, Dexter’s sister, Debra (Jennifer Carpenter), is investigating some family history and a couple of his co-workers are involved in an office romance.



The compelling opener is loaded with typical dry humor courtesy of Dexter’s narration and has a killer ending.



Not so novel



The “Californication” opener is less satisfactory and only partly because Moody’s longtime love, Karen (Natascha McElhone), literally phones in her lines after moving to New York for a job. That leaves bad boy novelist Hank (Duchovny) to deal by himself with one of TV’s more interesting, difficult and experimental teenagers, Becca (Madeleine Martin).



Becca befriends a classmate, Chelsea (Ellen Davis). Chelsea’s pretty mother, Felicia (Embeth Davidtz) is a college professor and her father, Stacy (Peter Gallagher), is a college dean.



It isn’t long before the very cool Hank is spreading his cynical, offensive and critical musings to college kids, to the disapproval of his 33-year-old teaching assistant Jill Robinson (Diane Farr). Knowing Hank, it shouldn’t be long before his lessons extend beyond class.



Meanwhile, Hank’s agent buddy Charlie Runkie (Evan Handler), is trying to win back his wife Marcy (Pamelo Adlon) while fending off the advances of his new heavyweight, foulmouthed and cartoonish boss, Sue Collini (Kathleen Turner).



The first two episodes set up the series for the usual amount of guilty-pleasure, sexual high jinks and soft porn, male fantasy humor. But Karen desperately needs to come home to make Hank vulnerable — and more interesting.



TV Reviews



“Grey’s Anatomy” ?? (Out of four) 9 tonight, Channel 7



“Dexter” ???



9 p. m. Sunday, Showtime



“Californication” ??



10 p. m. Sunday, Showtime