Deadwood (2004)

Sandy Reed, the sister of the missing explorer John Reed, joins the team to retrace her brother’s final path. Karina goes incognito to find out what the locals know about the Akakor myth. With his drone, Brennon notices what could be a subterranean entrance behind a massive waterfall. But to check if it’s connected to the lost city, someone will need to rappel 500 feet – right beside the plunging water.