Josh Gates travels to Kenya and Chicago's Field Museum to investigate one of history's most terrifying wildlife incidents: the 1898 rampage of two lions that reportedly killed 135 railroad workers building the Uganda Railway near Tsavo. The infamous "Man-Eaters of Tsavo" now stand preserved in the Field Museum's Hall of Mammals, their pelts and skulls purchased from British Colonel John Henry Patterson, who hunted and killed them after nine months of terror. Gates sets out to separate fact from legend, examining the animals' remains for forensic clues about their final meals, searching for Patterson's long-lost "cave of bones" supposedly filled with human remains, and joining modern wildlife rangers tracking a new pair of rogue lions threatening communities today.
Mainstream historians acknowledge the Tsavo attacks as real events during British colonial railway construction, though the death toll of 135 has been widely debated—some scholars suggest the actual number was significantly lower, possibly inflated in Patterson's 1907 memoir. The lions' unusual behavior—hunting humans persistently rather than as occasional prey—remains a subject of scientific inquiry, with theories ranging from injuries that made traditional hunting difficult to the availability of human remains from railway camp burials. The episode gains urgency by connecting this historical mystery to present-day conservation challenges, as researchers employ modern forensic analysis on the century-old specimens while wildlife rangers work to prevent new human-lion conflicts in Kenya's rapidly changing landscape.
Big Life Foundation Headquarters
Kenya · scientific
Gates meets Maasai warrior and elder Daniel Ole Sambu, head coordinator of Big Life's predator protection program, to learn how state-of-the-art satellite tracking technology is used to monitor rogue lions and prevent modern-day attacks on livestock and humans.
Field Museum of Natural History
United States · historical
Gates visits the Field Museum in Chicago to examine the mounted specimens and skulls of the Tsavo man-eaters, which have been on display for over a century. He meets with curators Julian Kerbis Peterhans and Tom Gnoske to review new forensic discoveries made from the lions' teeth, including human hair samples.
Maasai Livestock Attack Site (Tsavo region)
Kenya · mystery
Gates travels 30 miles with Big Life rangers to examine a freshly killed sheep belonging to Maasai livestock owner Ntawuasa Meeli, investigating whether the aggressive collared lion Osunash and a partner are responsible for a series of livestock killings that mirror the 1898 Tsavo attacks.
Mombasa
Kenya · historical
Gates arrives in Mombasa, retracing Colonel Patterson's 1898 arrival and the starting point of the Uganda Railway construction story. He travels through the city by tuk-tuk to reach the railway station.
Nocturnal Lion Tracking Site (Tsavo bush)
Kenya · scientific
Gates joins Big Life rangers and lion guardian biologist Jeremiah Somita Purka on a nighttime tracking operation using radio telemetry and thermal cameras to locate the collared lion Osunash and his companion, discovering two male lions traveling as a pair — mirroring the behavior of the 1898 Tsavo man-eaters.
Tsavo River
Kenya · historical
Gates and Julian Kerbis Peterhans hike down to the Tsavo River below the bridge to examine the terrain where the lion attacks occurred and discuss the historical events in detail.
Tsavo, Kenya
Kenya · historical
Josh investigates the rampage of two man-eating lions who killed up to 135 railroad workers in 1898, while also tracking modern-day rogue lions.
Voi
Kenya · historical
Gates disembarks the train at Voi, the nearest town to the Tsavo Bridge, before driving the remaining 32 miles to the historic site of the lion attacks.