Walking with Beasts, marketed as Walking with Prehistoric Beasts in North America, is a 2001 six-part nature documentary television miniseries created by Impossible Pictures and produced by the BBC Science Unit, the Discovery Channel, ProSieben and TV Asahi. The sequel to the 1999 miniseries Walking with Dinosaurs, Walking with Beasts explores the life in the Cenozoic era, after the extinction of the non-avian dinosaurs, particularly focusing on the rise of the mammals to dominance.

Sabre Tooth is the 5th episode of Walking with Beasts and follows Half-Tooth and his clan now ruled by The Brothers. The fifth episode explores the strange fauna of South America, by this point isolated for millions of years, and the effects of the Great American Interchange, which happened about 1.5 million years earlier. Among the strange animals inhabiting South America are the giant armored Doedicurus, the trunked and camel-like Macrauchenia, the giant ground sloth Megatherium and the terror bird Phorusrhacos. The episode particularly focuses on the sabre-toothed cat Smilodon populator, following a Smilodon nicknamed "Half Tooth" and his efforts to reclaim his clan and territory after being defeated and driven away by two rival male Smilodon. It also focuses on how Smilodon's 8-inch-long upper canines were too fragile to bite into bone, and how Smilodon could therefore eat only the more tender parts of its kill. Afterwards, Phorusrhacos would scavenge the remains of Smilodon kills.