When we arrive at the crime scene, barely any evidence remains. Only a few blood-soaked blades of grass, glistening in the tangerine dawn sunshine, reveal foul play has been afoot.

By now the perpetrators are long gone, having raced into the dense teak forest, so thick and lush in late spring. Yet only minutes earlier, "detective" Kanga and I had been hot on their tails, as urgent shrieks ripped through the Zambian bush and a very violent murder unfolded.

The only weapon I'm shooting with is a Nikon DSLR camera, but on a walking safari through the South Luangwa National Park, I find myself embroiled in a life or death drama far more thrilling than any Hollywood cop movie.

Accompanied by an armed ranger, we'd set off early that morning to explore areas of the park only accessible by foot. When super sleuth Kanga, who's been guiding for eight years, detects fresh leopard and wild dog paw prints in the sandy soil, we know predators must be close by - in reality, much closer than we imagine.

Bounding vertically like a bouncy ball, a male impala starts frantically stotting, a display to deter potential attackers, indicating he's being chased - most likely by a pack of wild dogs.

Panic spirals like a tornado as guinea fowl screech and opportunistic hooded vultures swoop down in anticipation of a fresh feed.

To our left, baboons are barking ferociously, a sign their nemesis, the leopard, must be in the vicinity. Sure enough, we see a flash of silky rosettes slinking through the undergrowth.

But there are far wilier criminals in the area. A shrill cry leads us to a clearing but by the time we arrive, the deed is already done.

Large ears pivoting like satellite dishes, the wild dogs have detected our presence. For a few minutes I stand 100 metres from them, staring eye to eye, before they cautiously trot away.

There's been a kill and we were in the middle of it, listening to every alarm call and sensing the rising panic, as if we were part of the chase.

If a classic vehicle safari concentrates on watching wildlife, then walking is all about feeling. Standing on a level playing field with wildlife, you're immediately part of their matrix and it's easy to see why experienced guides like Kanga prefer to cover ground with their own two feet.

South Luangwa is often cited as the birthplace of the walking safari, first offered by Norman Carr in the 1950s, with some of the most scenic terrain in Africa.

Forty years later, guide and safari camp owner Robin Pope began running mobile camping safaris, where guests would explore the bush by foot, sleeping at different spots every night.

I'm given a taster of the experience at an overnight bush camp, which is far more luxurious than it sounds. Along with a tent, long-drop toilet and bucket shower, I have a chef, waiters and even a well-stocked riverside bar at my disposal. Beneath the shade of mopane trees, I fall asleep listening to giggling hyenas and wake up to hippos honking and spluttering in the meandering Luangwa river, still flowing at the end of May.

Perhaps South Luangwa's greatest attraction is its landscape; oxbow lakes piled high with lime green Nile cabbage curl through dense teak forests. By September, much of the vegetation will have wilted away and riverbeds turned to dust, making game viewing arguably much easier. But with clearer air (none of the forest fires, which result in a semi-permanent cloud of smog, have started) and vibrant colours, there's something very beautiful about this season. The wildlife too seems equally abundant - creatures large and small.

Flashes of brilliant purple light up the sky as lilac-breasted rollers perform loop-the-loops, and at ground level, antlions litter the dry soil with conical-shaped booby traps to catch their prey, while white fortified bee eaters ruffle their feathers and take dust baths nearby.

A male puku - an antelope with a thick brown coat - peels back his lips in a Leslie Ash-style pout, to sniff a female's rear end and assess if she's on heat. Dissatisfied, he bounds away and applies his clunky seduction techniques elsewhere.

Having walked almost 10km, we stop to rest on a fallen tree trunk at a lagoon populated by Egyptian geese and African jacanas. Fierce commotion breaks the idyllic silence, as a gosling is pulled underwater by a stealthy crocodile, a reminder that it's survival of the fittest out here.

When we eventually arrive at Robin Pope's Nsefu camp, Zambia's first photographic safari camp, established by Norman Carr in the 1950s, fellow guests have covered more ground in their 4x4s, taken more photos and have, arguably, seen more than us. But I bet none have locked into the environment in quite the same way, sharing that visceral fear that keeps senses permanently on a knife-edge.

Robin Pope operates four camps in South Luangwa: Nkwali (with six chalets set on private land overlooking the park), Luangwa River Camp (an elegant home in the neighbouring Game Management Area with five brick and thatch freestanding suites), Tena Tena (a sumptuous tented camp shaded by mahogany trees) and Nsefu (with six rondavels swathed in history). The latter two camps are in a remote sector of the park, where few self-drive day-trippers venture.

One thing they all have in common, though, is an opportunity to spot leopards. These famously elusive cats are the star players of South Luangwa, and by the end of a week's stay I'm almost tripping over them.

During numerous game drives in elevated open-top vehicles, I watch a tough male carefully guarding his prey in the treetops, witness a hungry juvenile stalking puku in the bushes, and spend several hours with a surprisingly approachable female, as she glides slowly through the long grass, tracking an impala herd.

Most leopard sightings are at night, but Zambian park authorities permit drives until 8pm, meaning its possible to search with flashlights.

The proliferation of leopards in South Luangwa is largely due to a low lion population, with many prides fractured by past trophy hunting.

Since a countrywide ban was imposed in January 2013, numbers have improved, although it's feared plans to reintroduce big cat trophy hunting next year may result in a reversal of fortunes. In theory, hunters can only operate in bordering GMAs, but past cases of illegal baiting have affected prides in the park. Non-profit conservation trust The Zambian Carnivore Programme will closely monitor any impact.

The recent high profile case of Cecil the lion, in neighbouring Zimbabwe, has thrown the "sport" into the spotlight, with opinions divided on the financial benefits it can potentially bring to conservation.

I personally struggle to understand why anyone would want to kill an endangered animal (and across Africa, lions are in serious trouble). Another guest offers some explanation: "Perhaps they have a closer engagement with wildlife than you and I will ever have."

But I'd argue a walking safari stirs up those same emotions and feelings of connectivity; the only difference being that the trophies I plan to hang on my wall (and in South Luangwa there are many!) are photographic ones.

TRAVEL FACTS

:: Sarah Marshall was a guest of Expert Africa and Robin Pope Safaris. A nine-night/10-day day Hippo Safari costs from £4,219 pp (based on two sharing) and includes return overnight flights from Heathrow, seven nights' accommodation, all meals, most drinks, two safari activities per day, internal flights, transfers and park fees. Call Expert Africa on 020 8232 9777 or visit www.expertafrica.com. This classic Zambian safari in the South Luangwa National Park stays at three small, high-quality camps run by Robin Pope Safaris and allows you to choose your activities - from walking safaris to 4x4 game drives (night & day).