Romancing the Stone (1984)

Though she can spin wild tales of passionate romance, novelist Joan Wilder has no life of her own. Then one day adventure comes her way in the form of a mysterious package. It turns out that the parcel is the ransom she'll need to free her abducted sister, so Joan flies to South America to hand it over. But she gets on the wrong bus and winds up hopelessly stranded in the jungle.