Satan's Harvest (1970)

When his uncle is killed in a horrible animal attack, American detective Cutter Murdock arrives in South Africa to inherit his ranching empire. Murdock's Johannesburg homecoming begins with an unexpected bang as the Miami-based private eye steps off the plane and a shot rings out - a man standing nearby is killed. Another uncle, Craig, and his son Timothy, were passed over in the will but, in spite of this, have moved into the ranch. Cutter meets up with Marla Oaks, the daughter of an American game trapper and once again an attempt is made on his life. Soon afterward Cutter and his friend Bates are beaten up and left for dead at the bottom of a mine shaft. It turns out that Craig, Timothy and older brother Andrew are part of an international drug-smuggling outfit and the ranch Cutter has inherited is used to grow marijuana. This one makes "The Birds" look like "Citizen Kane."