Complex sentence: Butch Cassidy and Sundance Kid are also involved in this caper and they kidnap Goldie and steal his nugget but Scrooge eventually rescues Goldie and gets his nugget back.
Split into simpler sentences: Butch Cassidy and Sundance Kid are also involved in this caper; they kidnap Goldie and steal Scrooge's nugget. But Scrooge eventually rescues Goldie and gets his nugget back.