After 30 years, "Hawaii Five-0" returns to prime time on CBS with a grandly conceived reboot of the series that made television history as one of the longest-running police dramas. Its creators have said they want to tip their hat to the original while at the same time creating a fresh "Five-0," complete with character depth and the realism that marks the police genre.

Here’s our guide to "Hawaii Five-0," then and now.

Steve McGarrett

That was then: Played by Jack Lord, right, a 6-foot-tall New York native who worked as a merchant marine, studied fine art and appeared on Broadway. He was 47 when he took the part as the former Navy officer and law enforcer.

This is now: Alex O’Loughlin, above, a 6-foot-1 Australian whose previous TV roles include a vampire private detective and a doctor. The muscled 34-year-old O’Loughlin is a certified stuntman who says the new "Five-0" is physically demanding. Formerly with Navy special ops, the new McGarrett gets plenty of opportunities to display his mad skills in firearms and martial arts.

"We have a great stunt team and the boys do whatever we need them to do and whatever I can’t do or I am not insured to do," O’Loughlin said. "But there is still a lot of running around and heavy breathing for all of us."

The Bond between them: Lord starred in the first James Bond movie, "Dr. No," as CIA agent Felix Leiter in 1962, while O’Loughlin was a considered for the latest Bond incarnation; the part went to Daniel Craig.

Chin Ho Kelly

That was then: Kam Fong, right, a stocky, former Honolulu police officer-turned-actor, was the original Chin Ho Kelly. He was 50 when he was cast in "Five-0." At the time, he was one of state’s best-known character actors.

He’s famous now: Daniel Dae Kim, below, is probably the most recognizable actor in the new series, thanks to his role as Jin in the global hit ABC series "Lost." The 42-year-old Kim describes his character as a darker, more cynical version.

"He’s a combination of the aloha spirit mixed with some of the complications of the real world," Kim said.

Kono Kalakaua

That was then: The late Zulu, left, was a 31-year-old Waikiki beachboy when he was cast as Kono but he left after four seasons, chafing at what he described as too much "yes boss, no boss." On the show, McGarrett often dubbed him the "Big Kanaka." He went on to have a successful nightclub career.

She’s now: Grace Park, above, the 36-year-old fan favorite on the science fiction series "Battlestar Galactica," completely reinvents her character. Although no beachboy, the slender Park spends a lot of her screen time in the pilot on the beach in a bikini. But then again, this is not "Detroit Five-0."

Danny "Danno" Williams

That was then: Although the part of McGarrett’s trusted sidekick was played by Tim O’Kelly in the 1968 pilot, the regular series role went to James MacArthur, a prolific actor of Disney films, TV westerns and stage productions. He was 30 when he was cast.

Book ’em now: Scott Caan, 34, is redefining the part of Danno, bringing a wisecracking swagger to his character. He’s been in a variety of films and TV shows, from "Varsity Blues" to all three "Ocean’s" heist films and HBO’s "Entourage." His Danno is a relocated ex-New Jersey cop who prefers skyscrapers to beaches but moved to Hawaii to be near his 8-year-old daughter, who lives with his ex-wife.

A family affair: Both Dannos are the children of famous actors: MacArthur’s mother was the late stage and screen legend Helen Hayes and Caan’s father is James Caan of "Godfather" fame.

Mary Ann McGarrett

That was then: Yes, Steve McGarrett had a sister; she appeared in only one episode ("Once Upon a Time" in February 1969). The part was played by Nancy Malone and the episode involved the famous detective flying to Los Angeles to help his sis deal with her child’s cancer and a quack faith healer.

This is now: Taryn Manning, best known for her part as Nola in 2005’s "Hustle & Flow" with Oscar nominee Terrence Howard, will appear in the new series as McGarrett’s sister in a sibling relationship with some history. She said she is scheduled for at least seven to nine episodes.

"They brought her in to humanize McGarrett and to give him a past, a family — heart if you will," she said. "It’s been really great. They are sort of unfolding where she is going."

The governor

He’s in charge: Richard Denning was retired and living on Maui when Leonard Freeman persuaded the distinguished-looking actor to play the part of Hawaii Gov. Paul Jameson. The star of "Creature from the Black Lagoon" appeared in 69 episodes.

She’s the boss: Perhaps in a wink at Hawaii’s real Gov. Linda Lingle, the first woman to hold the job, the new "Five-0" features Emmy-winning Jean Smart as tough-talking Gov. Pat Jameson.

The medical examiner

The know-it-all: The old "Five-0" featured Al Eben as Doc Bergman in 54 episodes, but local resident Harry Endo is probably better remembered for his Che Fong, the forensic specialist who was supposed to know everything about everything and did just that in 114 episodes.

The quirky body guy: Beginning in the fourth episode, Masi Oka, who was Hiro on "Heroes," will appear as the Honolulu medical examiner. Oka told reporters last month his character — Max Bergman — is "an odd little man" who plays a piano in his autopsy room.

The bad guys

That was then: No question, the original "Five-0" had a long line of great villains. Several matched wits with McGarrett on a regular basis, including mob bosses Henore Vaschon (Harold Gould) and Tony Alika (Ross Martin) and a pimp named Big Chicken, who was played Gavin MacLeod, who later helmed "The Love Boat" as Capt. Stubing.

Undoubtedly, McGarrett’s greatest foe was Wo Fat, the Red Chinese agent introduced in the pilot and put behind bars 12 years later in the series finale. Wo Fat was played with deliciously evil intent by Khigh Dhiegh, a New Jersey native who was born Kenneth Dickerson. Although he played Asian roles throughout his career, Dhiegh was actually of Caucasian, Egyptian and Sudanese descent.

Who’s bad now: The pilot features book-end appearances by a Euro-trash terrorist named Victor Hesse, played by James Marsters of "Buffy the Vampire Slayer." He provides the impetus for the formation of the new outside-the-law "Five-0" team by murdering McGarrett’s father before the first commercial. (In the original series, McGarrett’s father was also a victim, run down by a supermarket robber.)

The new McGarrett — O’Loughlin — said "Five-0" won’t disappoint when it comes to villains.

"There are great bad guys in every episode," he said. "Some of them change and some of them just might come back — if you’re lucky."

The ride

Crazy ’bout a Mercury: Back in the day, Steve McGarrett chased criminals in a big black Mercury with so much horsepower, the tires squealed even in sand. When "Five-0" premiered, his ride was a 1968 Mercury Parklane Brougham. In 1974, he got the keys to a new Mercury Marquis. After the series finale, Jack Lord gave the car to his stunt double, John Nordlum of Nanakuli. Nordlum still owns the vehicle, which has more than 200,000 miles on it. Nordlum believes the spirit of Lord lives in it.

Modern horsepower: In the spirit of reinvention, the reboot of "Five-0" features the reboot of a classic American car, the Chevy Camaro. It’s Danno’s ride. The muscle car of the 1960s was retooled in 2010 and the stars of "Five-0" will cruise around in a silver 2011 version. McGarrett will drive something a bit more basic: a Chevy Silverado pickup truck.

Don’t blink: In the new "Five-0" pilot, McGarrett finds his father’s old car in the family garage and guess what? It’s the black Mercury owned by Nordlum.

HQ

Royal suite: In the late 1960s, ‘Iolani Palace wasn’t a museum so it wasn’t a problem to film scenes inside, where McGarrett and his crew had their headquarters.

Across the street: The new crew is set up in offices just across the street at the back of the U.S. Post Office. CBS also turned part of the old Honolulu Advertiser site into a soundstage.

The catchphrase

Same as it ever was: Nothing said "Hawaii Five-0" more than McGarrett’s show-closing instructions to his chief underling: "Book ’em, Danno." Decades later, James MacArthur said people still shout it out wherever he goes. As part of their homage to the original series, the signature phrase gets its due in the reboot, and in a show steeped in back story explanations of every character, even the phrase comes with its own little history.