A Line in the Dark by Malinda Lo

Book–Amateur comic book artist and high school student Jess Wong is painfully, unhealthily in love with her best friend Angie. Jess is content to obsess over Angie secretly until Angie enters into a relationship with Margot Adams, a beautiful student from the nearby posh boarding school. Naturally, Jess thinks Margot is no good for Angie, but is this just sour grapes on Jess’s part or is Margot really bad news? When tragedy strikes at an off-campus party and everyone is a suspect, Jess must face up to what really happened that night. Or must she?

This is a dark, twisty thriller, like Pretty Little Liars meets Gone Girl meets The L Word. The book is split in two parts: the beginning is told in first person from Jess’ POV and the end is made up of police interviews and third person limited POV following multiple characters. This allows Lo to build up the tension without giving it all away too quickly. If you enjoy A Line in the Dark, you might also like twisty young adult books like We Were Liars and Last Seen Leaving.