Elizabeth Dean Lail (born March 25, 1992) is an American actress. She is known for her starring roles as Amy Hughes in the 2016 Freeform television series Dead of Summer and as Guinevere Beck in the 2018 Lifetime television series You, and for her recurring role as Anna in the fourth season of the ABC adventure fantasy television series Once Upon a Time. Lail was born in Williamson County, Texas, to Dean Franklin Lail and Kay Lurene Surratt. She has one older sister. Lail grew up in Asheboro, North Carolina. After graduating from Asheboro High School in 2009, she attended the University of North Carolina School of the Arts, graduating in May 2014.