How well do you know your neighbour?Would you trust them with your life?I heard Emily before I saw her. The harsh smack of heels against cheap wooden floorboards. The loud phone calls. The incessant music.I knew Emily before I met her. Discarded receipts in our communal hallway. Sticky leftovers in the shared food waste bin. Wine shop vouchers in the letterbox.Now shes gone missing, and Im the only one who can find her. The only one who can save her.Because I know her best, and I heard everything.The Girl Upstairs is a spine-tingling psychological thriller of grief and obsession that explores how lonely London can be and how sometimes its our neighbours who see us most, who know us bestA must-read for fans of Lisa Jewell and Sarah Pinborough.