Hanging at a tavern outside, amid people dancing and having a knees-up, Edward uses eagle vision and spies the Thomson brothers joining in on the festivities, until our hooded pirate assassin friend smashes one them into the bar. Sometimes you eat the bar, and sometimes the bar eats you. Eat bar, Thomson! One down, the other to go, Thomson number two makes a break for it, running to his galleon at the docks. Sure, Edward could gun Thomson two down in cold blood with his flintlock pistol, but instead he gives chase in his own ship, the Jackdaw. All of this happens completely seamlessly with no loading whatsoever, and as Edward climbs aboard his ship, his crew snap into action. “Ahoy, captain!”

Aboard the Jackdaw, Edward can use his spyglass to see what cargo other vessels are carrying, and he can board the ships and plunder their bounty. Accruing resources from pillaged ships will enable Eddie to apply upgrades and customisation options to the Jackdaw, making it your own. Chasing down Thomson's galleon, Edward orders his crew to bombard the ship with cannon fire, smashing the masts to splinters, being careful to preserve the hull (each ship now has a health bar, so you can damage it just enough without sinking it) and the precious cargo. Rocking up aside the ship, you can launch grappling hooks to tether the two ships together, priming it for boarding.

Leaping across with your crew, Edward can protect his shipmates from snipers on high, before fighting off Thomson's soldiers and ultimately stabbing up the fat-faced, rosy-cheeked Thomson himself. Contract completed, it's time to salvage the rewards inside the ship's hull and either execute or recruit the surviving crew. Obviously, recruiting more shipmates to come aboard the Jackdaw is the savvy choice. You can manage your ship via the companion tablet app, engaging in the fleet mini-game for cargo and upgrades.

At this point, our Ubi rep shows us Assassin's Creed IV's full map, and it's far and away the largest AC open-world we've ever seen. It dwarves ACIII by some margin, but it's rich with detail and activity, and this next-gen build seems stable and glitch-free. We're not sure how the current-gen version of the game will measure up, but there's no shortage of ambition on show here, even if Ubisoft has committed Assassin's Creed to a yearly launch cycle.

Still at the helm of the Jackdaw, Edward sails onwards to a small island, where he finds the corpse of an unfortunate pirate marooned there, with small crabs feeding on it. Clutching a treasure map depicting a Mayan ruin, there's loot to be reaped. You can view the sketched treasure map through the mobile app too, so there's no need to constantly consult menus if you have a tablet device to hand. The map leads us to a place known as Misteriosa, where the Spanish have set up camp.

In Black Flag you'll not only find yourself rubbing shoulders with notorious pirates like Blackbeard and Calico Jack, but you might also find yourself caught between English and Spanish forces fighting, and like any good pirate this can be exploited and used to your advantage. Lead a chasing Spanish ship into an English armada or vice-versa for example, and you can watch as they decimate one another, leaving you free to take the spoils once the fracas has died down. Emergent encounters like these can happen randomly at any time.

During the journey to the island, we see a white whale (you can share whale locations with friends via the app) and as Edward dives off the boat into the Misteriosa island lagoon, dolphins swim in the deep waters. It's simply glorious. Prior to all of this, Edward sails the ship through a violent storm, where a water spout and lightning spectacularly blasts a ship to smithereens in front of us. Sailing into the comparative serenity of the Misteriosa bay, the towering Mayan ruin looms into view. Edward sets about isolating the Spanish captain, sniping him with a poison dart from his blowpipe. The captain goes berserk, slicing up his allies, leaving the way clear for Edward to climb the huge vine-covered structure.

Climbing through trees, hiding in the bushes and foliage, and ascending the creeping vines as lizards dart around, the jungle surrounding the ruin is teeming with life. You can almost feel the tropical Caribbean heat as Edward scales the white bricks, finding a collectible Animus fragment along the way. We don't currently know what these will do, but we imagine they'll form some sort of intriguing secret once you've located them all.

Inside the temple, Edward spots two Spanish guards holding two pirates hostage. Stealthily scurrying up one of the temple's ruined columns, he swoops from the air for a double execution, freeing the pirates who can then be added to the Jackdaw's swelling ranks.

At the temple's summit, the view is incredible, stretching all the way to the horizon. Finding the treasure's location near an ornate fountain and pool, Edward digs for his prize and uncovers a chest, housing a blueprint for heavy cannon shots that can be added to the Jackdaw, and a whole lot of gold. The journey turned out to be totally worthwhile, and the Misteriosa temple also becomes a new fast travel point. In such a vast world, you'll need plenty of these.

Assassin's Creed IV: Black Flag looks set to make good on Ubisoft's promise to take the series to another level of seamless open-world freedom, and this next-gen version of the game is truly impressive. For us, Assassin's Creed II remains the series' pinnacle, but based on this latest up-close and personal run through, Assassin's Creed IV: Black Flag might not be too far behind as far as moving the series forward is concerned. Hopefully, it's a pirate's life for us, if this is indicative of what's to come. Arr.