CBS has finally revealed the plot of the premiere episode of "Hawaii Five-0" season 7 one month befire it is aired.

According to the synopsis for the upcoming season, McGarrett (Alex O'Loughlin) will continue to be his usual steadfast self despite Danny's (Scott Caan) advice to take it easy while he is still recovering from surgery due to a life-threatening event at the end of season 6.

However, McGarrett will ignore his friend's plea after he finds out that a dead body of a serial killer with an ivory chess piece in his mouth suddenly appears in the team's headquarters.

The team will also get into a full investigation mode after another body of a serial killer is found with another chess piece. This will prompt the entire Five-0 to look for the vigilante who is responsible for the killings.

McGarrett's physical strength might not return 100 percent at the start of the season, but he will reportedly find comfort while talking with someone who has a very special connection with the team.

The network also revealed that two new recurring characters will be introduced in the upcoming season. They are Governor Keiko Mahoe, who will be portrayed by actress Rosalind Chao, and retired criminal profiler named Alicia Brown, to be portrayed by Claire Forlani.

Executive producer Peter Lenkov discussed Alicia's possible involvement in McGarrett's life in an interview with Entertainment Weekly, saying: "Alicia and McGarrett have a profound respect for each other and what they have accomplished professionally. Her insight and expertise as a profiler will be paramount for Five-0 to track down this killer menacing the Island for those who visit and those who call it their home."

Reports also revealed that McGarrett's mother, Doris (Christine Lahti), will return on the show's 150^th episode special. She is expected to take care of her injured son.

"Hawaii Five-0" season 7 is set to premiere on CBS on Sept. 23.