"Blue Bloods" season 7 is set to premiere on September 23 and fans are already excited to know what's in store for its characters.

The preview for the upcoming season sets up what may be the most important premiere episode for the series that viewers may have seen since the show debuted.

While it's one thing to have to kill someone while on duty, it's another thing to kill someone when the target person is or is not armed. This is the dilemma that Danny Reagan is faced with as he faces Thomas Wilder, the serial killer that he tried to take down with a shot in the previous season.

It can be recalled that in that moment, before the shooting incident, Wilder tried to make him believe that he had a gun. Some viewers may argue that Reagan simply acted in self-defense fearing for his life.

At the same time, however, it is very clear that when he shot Wilder, revenge was on his mind. Also, some new pieces of evidence may lead to some further interrogations as to whether or not the shooting incident was really murder. Reagan may need the help of his family as he prepares for the series of interrogations, since his future could be on the line if anything goes the wrong way.

Fans may hate to see the negative spotlight on Danny in the new season, but it is also good to know that the producers are making him face his past as it helps make the series feel truer to life.

"Blue Bloods" returns on Sept. 23 on CBS.