In the rainy season, the 4,000-mile river crashes over its banks, turning entire forests into inland seas and camouflaging many of the dangers that lurk beneath.

It was rainy season in the Peruvian Amazon and we were told there was little dry land in the region. This was easy to believe, with the swollen river tossing whole trees like twigs down its miles-wide torrent. But as our skiff rounded a tributary, a large swath of lawn emerged, dotted with tufts of springy grass. The too-bright stretch of lime called to me from the boat, begging me to bound down its lush length.

As my eyes adjusted, I realized that this seemingly solid carpet of green was actually a large, dense grouping of water hyacinth, throbbing with electric blue and crimson dragonflies, spindly mottled spiders and monstrous ants. The rare break in vegetation revealed the river’s inky black water, where anaconda, piranha and alligator-like caiman lurked beneath.

The Amazon is a river of extremes. It cuts a 4,000 mile path from the Andes to the Atlantic Ocean -- longer than the distance between New York City and Berlin. During the rainy season, the Amazon crashes over its banks, turning entire forests into inland seas and swelling to an average of 28 miles wide along its inland length and 300 miles wide at its mouth.

Everything here is a little too saturated, a little too bright, a little too dense. Like a camera attempting to focus, your eyes constantly zoom in and out, pinballing around to try to process the technicolour birds, the impenetrable walls of green and the swarms of otherworldly insects -- much of which is reflected like a fairground mirror in the obsidian slate of the river’s black water.

It is easy to understand how countless streams of explorers were lured deep into this region, convinced that another few days or another few miles would open up its mysteries. But as 19th-century explorer Percy Fawcett said, nature here is “against man as it is nowhere else in the world” (Fawcett was no exception, mysteriously vanishing into its depths in 1925, never to be heard from again).

Almost a century later, the Amazon remains one of the last truly wild regions of the world. But these days, you can explore it with protection from the elements in the form of the M/V Aqua, the first luxury ship to ply these wild waters. During the three-, four- and seven-night cruises through the Peruvian Amazon, the ship’s 12 rooms provide respite from the sensory assault of the river, cinematically framing its churning waters with floor-to-ceiling windows, cocooning you in air-conditioned cabins of Brazilian slate and Amazonian hardwoods, and using local flora and fauna in innovative tasting menus designed by Peruvian master chef Pedro Miguel Schiaffino.

While the boat allows you to sleep in total comfort, the river cruise is far from adventure light. On our first day of exploration, we boarded small skiffs and headed up the Tahuayo tributary in search of wildlife. The rainforest made good on its name, pouring down until we hacked through the underbrush into a canopy-covered lagoon. Beneath the waters swam the dreaded red-bellied piranha, the pack-hunting fish whose jagged teeth can strip the flesh from an animal in minutes. Our M/V Aqua guide, Ricardo, bravely pried open one fish’s mouth, baring its razor sharp fangs. This was just the first in a near-comical procession of lurking horrors — from anaconda that can digest an entire deer to the slivery candiru (parasitic toothpick fish) that can lodge, die and rot in your urethra, from puraques (eels) that can send 650 volts of electricity into their prey to bullet ants whose stings feel like being shot (all dangers we thankfully avoided).

But for all the terrors of the rainforest, it is equally rewarding in its beauty. The next day in the five-million acre Pacaya-Samiria National Reserve, the sun burned bright, giving an electric glow to the throbbing canopy where parakeets swooped, sloths napped and tamarind and red howler monkeys played. It was all reflected in the smooth surface of the water, coloured a coffee-black by tannins released from decaying plant life below. The surface became a dark mirror as we cut the motors, taking in the guttural whoops, whines, trills and clicks around us. Then a shimmering pink snout and an iridescent fin broke the surface, revealing the rainforest’s most mythical creature: the pink river dolphin. Local legend holds that the dolphins shapeshift into handsome men at night to lure beautiful women from the villages. It was easy to believe the tale as another crested, then another, striping the river with shimmering streaks of rosy blush.   

Like untold numbers before, I was slowly seduced by the Amazon’s violent wilderness, its outlandish wonders daring me to go deeper. After all, if something as seemingly delicate as that school of dolphins could glide beneath the surface, surely I could too. Calling my bluff, Ricardo navigated into a flat stretch of water and told me to check my skin for open cuts (piranha bait). I leapt in, away from the searing heat of the midday sun to the cool relief below. I bobbed downstream, buoyed by the thrill of danger, awed that so simple an act as swimming could hold such innumerable threats. But the Amazon let me have my fun, carrying me and my brave travelling companions downstream without incident. We climbed back onboard, sopping and smiling, greeted by the bemused Ricardo. 

To him, a lifelong resident in this region, our nervous dip was a silly lark. Wildlife may be the area’s primary draw, but the true wonder of the Amazon is the ingenuity and adaptability of the estimated 350 indigenous and ethnic groups that live off this unsympathetic land. In the small village of Puerto Miguel, we met the teacher who travels days by boat to visit the village’s small school, the children who help their parents gather fruit and fish, and the pet monkey who naughtily nibbles at the necklaces local women have crafted to sell. The locals guided us on foot through the rainforest, pointing out the ants whose pinchers they use for stitches, the trees whose sap works like iodine and the termites that can be crushed into mosquito repellent. Suddenly this hostile land felt ripe with the possibilities of healing. Another set of mysteries beneath another canopy of green.