Jones and Mutt are captured by Mac and the Soviets and taken to their camp in the Amazon jungle, where they find Oxley and Mutt's mother, Marion Ravenwood, who reveals that Mutt is Jones's son, Henry Jones III. Spalko believes the crystal skull belongs to an alien life form and holds great psychic power, and that finding more skulls in Akator will grant the Soviets the advantage of psychic warfare. Spalko uses the skull on Jones to enable him to understand Oxley and identify a route to Akator. Jones and his four allies escape with the skull, but Marion and Jones get caught into a dry sandpit, to be recaptured by the Soviets after Oxley accidentally brings them as assistance. On their way to Akator, Mac tells Jones he is a CIA double-agent to regain Jones's trust, and Jones's team fights its way out of the Soviets' clutches, while Dovchenko is devoured by siafu ants. Jones and his allies cause many of the Soviets to fall from a cliff, and they survive three waterfalls in an amphibious vehicle. Jones and Oxley identify a skull-like rock formation that leads them to Akator, unaware that Mac lied about being a CIA agent, is still loyal to Spalko and has been dropping transceivers to allow the surviving Soviets to track them.