Katherine Langford and Dylan Minnette went from up-and-coming actors [1] to full-blown superstars in the space of a few weeks thanks to their starring roles in 13 Reasons Why [2], which they opened up about while making their talk-show debut with Ellen DeGeneres [3] on Monday. Katherine revealed the Lady Gaga fangirl moment [4] that left her "shook as f*ck," while Dylan discussed why he had to literally "run away" from fans of the show at Coachella. Ellen also took the time to celebrate Katherine's 21st birthday with the surprise of a lifetime, so fingers crossed we see some selfies with Mother Monster on her Instagram [5] soon.