The news cycle took a dark turn this week with the massacre at a social services center in San Bernardino, California that left 14 dead and 21 wounded, spurring a manhunt and ensuing shootout that left two suspects dead.

The FBI is still trying to determine what motivated Syed Rizwan Farook, 28, and his wife, Tashfeen Malik, 27, to attack the center. Law enforcement sources tell CBS News that Farook was in contact with an people in the U.S. and overseas who have links to terrorism. CBS News has also confirmed that Malik pledged her allegiance to the Islamic State of Iraq and Syria (ISIS) online before the massacre.

The shooting has already made its mark on the 2016 election, leading some GOP candidates to raise the specter of homegrown terrorism. We'll talk with Republican frontrunner Donald Trump about the shooting - what is the significance of the massacre in California? And what can be done to reduce the chance of another such shooting in the future?

We'll also talk with Trump's fellow GOP candidate, New Jersey Gov. Chris Christie, who's touted his experience prosecuting terrorists and his hawkish foreign policy views on the stump. Could rising concerns about security in the U.S. provide Christie an opening to vault his campaign into contention?

On the Democratic side, we'll talk to Vermont Sen. Bernie Sandersto get his reaction to the massacre in San Bernardino, and to discuss how he sees the primary race shaping up as the year comes to a close.

We'll sit down with CBS News Senior Security Contributor Michael Morell, the former Deputy Director of the CIA, to discuss the homeland security concerns sparked by the shooting - what does he think of reports that the attackers were inspired by extremists abroad? And how vulnerable is the United States to these types of attacks?

Finally, we'll break it all down with an expert panel, including, Gwen Ifill of the PBS NewsHour, Ed O'Keefe of the Washington Post, CBS News Political Analyst and Slate Chief Political Correspondent Jamelle Bouie, Ben Domenech of the Federalist, and The Wall Street Journal's Jerry Seib.

It's going to be an exciting broadcast, so we hope you'll join us! Check your local listings for airtimes.