VIDEO : Throwback Thursday with Mandy Moore & Justin Timberlake

Mandy Moore shared a throwback photo with Justin Timberlake from the summer of 1999 that has fans abuzz The pic, which Moore explained was the time of "Abercrombie t-shirts and bucket hats," as she captioned the photo, adding, "Opening for this guy and his band. Look at my nervous smile!" So why the big deal? The pair are very Relevant Right Now: From her role on This Is Us to his latest round of awards show appearances, they've been everywhere lately.