The season 6 finale of ABC hit show "Castle" will be airing tonight.

The official synopsis for the finale episode titled "For Better or Worse" is as follows: "A secret investigation conducted by Beckett related to her mother's murder goes awry when a man she has been surveilling is killed. When evidence links Beckett to the victim, she and Castle become the targets of a manhunt that puts both of them in grave danger."

In tonight's episode, Kate Beckett will find out that she has been married to bartender Rogan O'Leary for 15 years. Her new discovery is made just days before her wedding to Rick Castle and she will need to get a divorce from her legal husband before the big day. She does not remember much, but thinks she tied the knot with O'Leary during a drunken night out in Las Vegas.

To proceed with the big day, Beckett will need to submit divorce papers. Fans will have to wait and see if Beckett manages to successfully file for divorce in time to tie the knot with Castle.

Be sure to tune in to ABC at 10 p.m. to catch the finale episode. If you miss tonight's episode, the show will be available to view online on ABC.com.

The ABC drama has been renewed for season 7, with a premiere date set for this fall.

Watch a preview video of "Castle" season 6 finale below: