sentences:  Booth tells Brennan that they have a major case and that FBI Deputy Director Cullen is going to want to set up a special unit to investigate.To do everything by the book he wants her to stay at her lab; but Brennan coerces Booth into agreeing to let her come with him into the field.Based on the particulates embedded in Cleo's skull, Hodgins determines that Cleo's skull may have been smashed by a sledgehammer on a cement floor with diatomaceous earth.