Hawaii Five-0's Steve McGarrett is back in action, much to Danny's chagrin.

The former Navy SEAL nearly lost his life at the end of season 6, and it was only Danno's (Scott Caan) quick thinking and matching blood type that kept McGarrett (Alex O'Loughlin) from going into the light. Now housing half of his partner's liver, Steve will jump back into the fray ahead of schedule when a serial killer starts delivering bodies to Five-0's HQ.

Titled "Makaukau 'oe e Pa'ani? (Ready to Play?)," the season 7 premiere will hit CBS tonight.

"When the bodies of two serial killers are found on Five-0 property with chess pieces in their mouths, McGarrett and the team hunt for a vigilante as fear grows that tourists aren't safe in Hawaii," CBS teased.

So who is this new villain? Expect him/her to be "Somebody a little bit more cerebral, a little bit more complex than anybody that we've dealt with before," according to showrunner Peter Lenkov.

It comes as no surprise that McGarrett will push himself too far. Where once he thought he was indestructible, the unstoppable cop will start to learn that he can't keep throwing himself off buildings with reckless abandon. It's a lesson everyone on the task force will mull over in the wake of last season's crash landing, and it could lead to some personal changes for a few of our heroes.

"It's sort of a theme that we start," showrunner Peter Lenkov told TV Guide. "Everybody in one way or another starts looking at the bigger picture in their lives, and how to fill some of those holes. There's more to being than just their jobs. So people are going to expand their lives a little bit more this season, and I think it starts with McGarrett just being reflective over what happened last season."

Catch Hawaii Five-0 at 9 p.m. ET on CBS or click here to live stream the episode with CBS Live.

Tags: Hawaii Five-O television CBS