The demonologist

"Professor David Ullman's expertise on Milton's Paradise Lost lands him a lucrative offer to travel to Venice and provide his professional opinion on a mysterious phenomenon. Intrigued, David heads to Italy with his 12-year-old daughter Tess--but soon after arrival, he finds himself waging a terrifying struggle to reclaim Tess from the Unnamed, a demonic force that wants David as its messenger."@en
"During a visit to Venice, Professor David Ullman--one of the world's leading authorities on demonic literature--witnesses a terror in a tiny attic room. Then his 12-year-old daughter Tess disappears before his eyes, and he must find her while confronting an unspeakable darkness along the way."
"A Columbia professor with expertise in demonic literature--specifically Milton's 'Paradise Lost'--is invited to Venice, Italy to witness a 'phenomenon' and offer his professional opinion for an enormous sum of money. While there, a demonic entity known as the Unnamed possesses his daughter, and he must rescue her from the Underworld."@en
"A Columbia professor with expertise in demonic literature--specifically Milton's 'Paradise Lost'--is invited to Venice, Italy to witness a 'phenomenon' and offer his professional opinion for an enormous sum of money. While there, a demonic entity known as the Unnamed possesses his daughter, and he must rescue her from the Underworld."