The Reagans are back on the case in this explosive sixth season of 'Blue Bloods'. The threat has never been greater as Frank (Tom Selleck) suspects New York City to be the next target for a terrorist attack. Meanwhile, his son Danny (Donnie Wahlberg) must track down dangerous targets of his own - serial murderers, cop killers, prison escapees - all while his brother Jamie (Will Estes) works to put the most heinous criminals behind bars, and their D.A. sister Erin (Bridget Moynahan) does everything she can to keep them there. When it comes to crime, nothing gets by this family.