Jason Lightwood: The last hour

Jason Lightwood: The last hour is a book about the ever prophesized third world war, except it's not what it appears. In the midst of a murder trial, Jason Lightwood must solve the 13 murders in England, work out why there are no adults left in London,  rescue his best friend from the depths of the houses of Parliament, and make it back in time for dinner, that is if his family are still alive.