Florida’s Palm Beach County features a cast of thousands, but the stars of the show are lemon sharks, goliath grouper, turtles and some of the best diving that can be had without a passport.

I’m rolling down Florida’s A1A Scenic and Historic Coastal Byway in an expensive ride that I’m sworn not to reveal (security reasons from a past life, I’m told). The top is down, the late-afternoon sun is gentle, and I’m straining to hear every word the big man says as Jimmy Buffett serenades us from the stereo.

It all seems perfect, especially since the maestro of Margaritaville christened an album A1A. But that was boozy Key West. This is its elegant cousin to the north, Palm Beach County, where the palm-fringed highway is populated by Bentleys and Mercedes, and sugar-white beaches lead to a seductive blue ocean where perfect diving reputedly exists.

“This is it, I’m tellin’ ya,” declares my driver, William “Taz” Tuzinsky, who looks at me for implicit agreement. See, Taz is the big man behind Scuba Center Delray, the PADI Dive Center the imposing ex-Detroit detective opened in 1999 after leaving a law-enforcement tec-diving career that included body retrievals and murder investigations. Since trading murky quarries and rivers for the South Florida coast, Taz has become a salesman. “So many divers think you need to travel the world to experience quality diving, right? I take them out, they dive in a gentle current alongside sharks, manta rays, turtles and corals, and then they’re gushing about how Palm Beach County is a better deal than plopping down $5,000 for exotic foreign dive vacations. Know what I mean?”

Well, no. I’ve always been a passport diver — the kind Taz is used to seeing. But my US of A redemption is about to begin in Delray Beach, where I’ll launch my mobile diving marathon. It’s a simple proposition since scores of dive sites are barely 10 minutes offshore. And heck, with so many marinas in Palm Beach County, you can barely fall off a gangplank without landing on another dive boat. If seeing is believing, let the show begin.

Act One: The Delray Way

The next day, Taz makes me a believer when I see a 10-foot hammerhead shark within the first few seconds of hitting the water at Boynton Reef. That’s followed by two portly loggerhead turtles, hubcap-size French angels and a supporting cast of marine life that make me swear I’m diving in some exotic fantasy waters that require a passport. When a 10-foot sailfish drifts 20 feet away during my safety stop — something I’ve never experienced in Central America, the South Pacific, the Caribbean — my first-ever dive in the waters of South Florida’s Palm Beach County seems like something along the lines of an epiphany. As a landlocked diver used to logging considerable air miles for foreign dive travel, this is something I could get used to.

• Related: Our travel guide to Palm Beach County

But Boynton Reef is only one of scores of named dive sites scattered along county waters. Shallow dives like Pink House, Cable Crossing and Ballentine’s represent the tip of the iceberg, all chock-full of ledges, corals and schooling reef fish. And if it’s wrecks you want, you’ve come to the right place: the Danny, Princess Anne, Atlantis and the Mizpah Wreck Corridor — the crème de la crème — comprise a litany of sunken ships, new and old, that could take weeks to fully explore.

Taz aims our 38-foot Loggerhead south to nearby Delray Ledges. The angular symmetry here is uncanny — nature’s own Reef Building 101 — with a complex of natural limestone blocks and walls running as shallow as 45 feet deep on the inside edge, and spilling to 85 feet deep on the bluewater side. We split the difference, drop to 60 feet, and scoot along at about 4 knots over a lush garden of barrel sponges, gorgonians, and 15-foot-high ledges with shadowed alcoves of snapper and jacks illuminated by glinting sunlight. Along our flight path we mosey by several lemon sharks and nurse sharks snoozing beneath ledges. With a mile behind our flippers, we call the dive just as a green sea turtle that’s been riding the current 30 feet off our port side angles down to dig into a healthy patch of sea grass swaying in the current — the day’s final act.

Act Two: Jupiter’s Constellation

The next morning, I’m tooling along the A1A to my day’s dive rendezvous an hour north in Jupiter. Between the waterfront estates, gorgeous beaches, swaying palms, trendy al fresco cafes and beautiful people, the opulence is nearly palpable. Even the pet dogs are meticulously coifed. Sure, the price of admission here brings pure sticker shock, but so far the diving is spectacularly equal-opportunity — a bargain considering the variety, quality and convenience.

The theme continues when I meet dive guide Philip Berg at the PADI Five Star Jupiter Dive Center and learn about the town’s four-for-one deal: world-class seasonal aggregations of lemon sharks (January-February), marine turtles (May-June), goliath grouper (August-September) and lobsters (late spring and summer).

“Everything that’s good about diving here exists because of the Gulf Stream. Manta rays, goliath grouper, tons of sharks, invertebrates, hard and soft corals — we’ve got it all,” Berg says about today’s possibilities. “Goliath grouper and lemon sharks are huge here. We get destination divers from all over the world who come for these alone.”

We kick off the day’s diving with a 1-mile drift beginning at Captain Mike’s and continuing past Area 51 to the northern edge of Juno Ledge. With a dozen of my new dive buddies — many from Europe — I giant-stride off the 42-foot Wet Temptation, fin diagonally, maneuver between ledges and peek into fishy grottoes where, as promised, we seem to see it all — at least by my reckoning. But the show’s just beginning. Berg bangs his tank every minute to get my attention. On the bluewater side facing the current, a couple of blacktip reef sharks; squeezed beneath ledges, nurse sharks; meandering through the sea grass, goliath grouper and loggerhead and green turtles. Add to these schools of blue runners, parrotfish galore, humongous barrel sponges, and colonies of sea whips and fans, and the species count rivals my better Caribbean dives. As if on cue, green morays and schools of large barracuda and horse-eye jacks make a cameo appearance during our safety stop at Juno Ledge.

A couple more dives out of Jupiter are just as rocking. We continue the trajectory of our earlier dive when we drop in at Spadefish, trading abrupt ledges for a gentle slope leading to a hard, steep wall. There are sharks, turtles, green morays and reef fish galore. But it’s our final dive at Bluffs, regarded as Jupiter’s prettiest, that is the real showstopper. Intermittent white-sand patches have settled upon the ancient riverbed, creating a series of separate cul-de-sacs that seem like fishy aquariums perfect for curious divers. Napping loggerheads are parked in one alcove, while a small hawksbill grazes on sponges in another. Flying along in the current, we watch a large eagle ray flittering its fin wings in the sand, and dead ahead a lemon shark cruises above a ledge. With shafts of sunlight piercing the depths like spotlights, colorful angelfish, wrasse, blennies and parrotfish sparkle as if they were gems in a jewelry box.

Act Three: Palm Beach Showstoppers

It’s no exaggeration to say the Blue Heron Bridge at Phil Foster Park is a Palm Beach County dive you shouldn’t miss. It’s renowned as one of the world’s premier macro sites, with a critter list that’s never-ending. It so happens this macro mecca is within spitting distance of my final dive appointment with Jim Abernethy, head honcho at Scuba Adventures in nearby Lake Park, Florida. When I ask about Blue Heron, Abernethy breaks the bad news. “Not today. It’s a little tricky. You have to stay clear of the boat channel and need to enter just before high slack tide,” he explains as we suit up aboard M/V Deep Obsession. But my dejection doesn’t last long. Within 15 minutes, we’re gliding over crystalline water where the viz is easily 100 feet. “This is one of the best dives in Palm Beach County: the Corridor,” says Abernethy. A quick look at the dive profile shows why. The 1,700-foot drift dive encompasses three wrecks, two rock piles and reef slabs home to all sorts of living marine treasures, including one affable goliath grouper that divers have nicknamed Shadow.

Dropping to 85 feet, the current quickly ushers us to the Mizpah, a 185-foot, three-level Greek luxury liner that’s seen better days. As Abernethy goes bonkers with his twin-strobe camera, I poke around and enjoy the menagerie of stingrays, eels, several turtles, and masses of fish swarming around the wreck and reef ledges. With this marine bounty, it’s easy to get caught up in the moment and simply lollygag, but Abernethy prods me along and we drift over the wreck of the 160-foot PC-1174 patrol vessel, then toward small protruding reef ledges and rock piles. As I survey the new surroundings, something big in the gauzy distance catches my eye. It’s not sleek like a shark or oval like a turtle. But it’s coming this way. Fast. I glance at Abernethy, who’s already spelled it out on his diver’s slate: Shadow the goliath grouper has arrived.

There’s a school of thought that says you should refrain from interacting with marine life. I get that. But Shadow might be the best exception to the rule. This 400-pound grouper has become a revered mascot for goliaths throughout the area, and its interactions with divers has helped buoy the profile of the species. What’s important to know is that Epinephelus itajara, which can grow to 10 feet long and 800 pounds, was nearly wiped out by decades of over-harvesting, until fishing the species was banned in 1990. The strategy worked, but that success has prompted talk of lifting the ban — a big concern in the South Florida diving community. Shadow certainly has an affinity for divers. And it seems it’s a bit of an exhibitionist as well. The mammoth grouper makes numerous swimbys as Abernethy goes full paparazzo with his big camera rig, strobes flashing away.

Shadow swings my direction and rubs me with its burly scales, begging for scratches I suppose. It’s tempting, but I don’t take the bait and simply stay put while Shadow weaves among other more-accommodating divers. It’s a duet between species, a rare moment of connection almost anywhere else but here. It’s a show worth seeing, and you don’t need a passport.

Dive Operators:
Scuba Center Delray scubacenterdelray.com

Jupiter Dive Center jupiterdivecenter.com

Jim Abernethy’s Scuba Adventures scuba-adventures.com