'Cortez the Killer' by Neil Young and 'Rank Strangers' by The Stanley Brothers are the songs that changed it all for Gillian Welch and David Rawlings. The pair have developed a deeply intuitive connection since meeting at college in the early '90s. They even finish each others' sentences. Their music is driven by spontaneous inspiration, the power of the things they leave out, and these two key songs that helped their artistic development.