The Shield reunion is undoubtedly the biggest storyline in the WWE right now.Roman Reigns, Dean Ambrose and Seth Rollins have reunited to deal with some common enemies and are set to face The Miz, Sheamus & Cesaro, Braun Strowman and, as of Monday, Kane.The Big Red Machine interfered in Reigns' cage match with Strowman before the Intercontinental champion, Miz, announced they had recruited Kane onto their side for the TLC pay-per-view.The build to the full-blown Shield reunion has been slow and methodical.The faction first rose to prominence at Survivor Series in 2012 when they powerbombed Ryback through an announce table in what has since become a signature of theirs.They would split in 2014 after Rollins turned on his brothers to align with Triple H and The Authority, but now that every man has become a world champion - a total of six reigns between them - three years later they have become the Hounds of Justice once more.The group appeared as a bona fide trio on the October 9 edition of Monday Night Raw, but it was only last Monday that they finally truly reverted back to old ways.The Shield's old music hit, they arrived in their old tactical gear and they made their entrance through the crowd.They were interrupting Raw general manager Kurt Angle's in-ring promo, but, unfortunately, the Olympic Hero failed to hear the signal and ruined the impact of the old music a little bit. Take a look below:

Fans have been wondering why Kane has returned out of nowhere to take part in this contest with the Shield and some outlets have speculated that it's his way of getting revenge on Reigns for retiring his brother, The Undertaker.

It's well known that the Devil's Favourite Demon is running for mayor of Knox County in Tennessee. He is only available in a part-time capacity and considering his campaign will come to a head next year, there's no way this is set to be a long run.

Whether 'Taker comes out of his assumed and implied retirement to take part in this angle remains to be seen, but the introduction of Kane seems strange if he doesn't.