Mortal Instruments revolves around Clary Fray (Lily Collins, Mirror Mirror), an ordinary teenager living in modern New York City, who discovers the truth about her lineage after her mother (Lena Headey, Game of Thrones) mysteriously vanishes: namely, that she is a descendant of the Shadowhunters, a legion of half-angel warriors who (in secret) protect humanity from the forces of darkness. Soon thereafter, young Clary begins her training as a demon-destroyer, with assistance from Hodge Starkweather (Jared Harris, Mad Men) – who is the elder caretaker at the Shadowhunter Institute - and the handsome-but-deadly warrior Jace Wayland (Jamie Cambell Bower, Camelot).
As you undoubtedly picked up from the synopsis and trailer, Mortal Instruments (in essence) uses the same fantasy/coming-of-age formula as the Harry Potter, Percy Jackson, and The Dark Is Rising series - but with a female, rather than male, teen protagonist. In terms of visual sophistication, Mortal Instruments does seem to be a slight improvement on the first Percy Jackson and first couple of Harry Potter films – though, it’s far behind latter installments in the Potter series. Bear in mind, it’s impossible to judge fully right now, as production quite literally wrapped up a matter of days ago (hence, there are no CGI shots in the trailer).