His financial position in the early 1970s gave him some basis for the belief that he could fund such a project. He had been the executive producer of The Exorcist (1973), one of the most commercially successful films in Hollywood history. The Exorcist had been adapted from William Peter Blatty’s novel — Blatty had been one of Marshall’s clients as an agent — and Marshall had brought the project to Warner Bros. The film’s commercial performance had given him both professional credibility and, presumably, a degree of financial capital that could be applied to the next project.
The next project was lions.
The script that Marshall developed followed a naturalist living on a wildlife preserve in Africa — the film’s version of the game warden’s house that had inspired the whole enterprise — whose family arrives for a visit to find the property occupied by wild animals. The naturalist has made his peace with the lions; the family has not, and much of the film’s action involves the family trying to survive the animals while the naturalist tries to negotiate between them. Marshall cast himself as the naturalist. He cast Hedren as his wife. He cast his sons John and Jerry as the family’s sons. And he cast Melanie Griffith as the daughter.
The animals accumulated gradually. The family acquired lions from zoos and circuses, which in the early 1970s were institutions that sometimes transferred their large cats to private parties willing to take them. They acquired tigers. They acquired leopards, cougars, jaguars. They eventually acquired an elephant named Timbo. By the time principal photography began in earnest in 1976 — six years after the concept had been formed — the animal cast had grown to extraordinary size. Different accounts of the final count vary, but by the time filming was underway, somewhere between 100 and 150 large cats were housed on the property.