The silly season is almost over but just when you thought it was safe to go back into cinemas, along comes The Mortal Instruments: City of Bones to spoil your day.
This Twilight wannabe, based on the first in a series of urban fantasy novels by Cassandra Clare, is instead a case study on how not to do it for moviemakers in search of a lucrative franchise to nurture.
The teenage/young adult market has proven to be wildly successful in recent years, with movies based on the books of Stephenie Meyer (Twilight) and Suzanne Collins (The Hunger Games) cleaning up at the boxoffice while chasing after the mother of all book-movie combinations, J K Rowling's Harry Potter series.
The Mortal Instruments has the requisite parts in place for a similar assault on the box-office: a secret world within one populated by ordinary humans, a feisty-but-conflicted heroine with a couple of romantic options at her disposal, plus the usual assortment of warlocks and werewolves, vampires and demons to force the pace.
Unfortunately, the latest addition to an increasingly crowded genre is no serious threat to Harry and pals, or even Bella and Edward - at least from a cinema-goer's perspective.
This movie is likely to win some diehard fans, but anyone else in search of a brave new series to commit to will be sorely disappointed.
The Mortal Instruments is a surprisingly sloppy piece of work.
Among its limitations is a lack of imagination from director Harald Zwart, a thoroughly pedestrian script by Jessica Postigo Pacquette and a cast that is mostly forgettable.