Hawaii Five-O
Hawaii Five-OFacebook/Hawaii Five-O

After the explosive season 6 premiere of "Hawaii Five-0", the show is maintaining its momentum with yet another thrilling plot that involves Jason Sinclair, the arsonist who was locked away in season 5.

The second episode of "Hawaii Five-O" season 6 is entitled "Lehu a Lehu" (Ashes to Ashes) and it will see a bomb squad being attacked by someone who wants Sinclair to be released.

This will force McGarrett and Danny to head to Halawa to see if Sinclair can identify the person who is demanding his release. However, the prisoner won't be as co-operative as they want him to be.

Meanwhile, McGarrett will be getting ready to pop the question to Catherine in true Navy Seal fashion."I've been planning the op," McGarrett tells Danny. "I secured a ring. I reconed a location. Now I've just got to execute."

Deciding to take his relationship with Catherine to the next level is one of the bravest things McGarrett has ever done. However, McGarrett and Catherine's relationship is going to be rocked by the presence of Lynn, a nature lover.

"You may have heard that Sarah Carter is coming in as Lynn, a nature lover with whom McGarrett goes on a wild adventure. Let's just say that it's going to be a busy fall for our head of Five-0," executive producer Peter Lenkov told Entertainment Weekly before the season premiere of "Hawaii Five-O."

The official synopsis of "Lehu a Lehu" reads:

A bomb squad is attacked and the culprit threatens to detonate additional explosives unless arsonist Jason Sinclair is released from prison. Meanwhile, Adam returns from the hospital and Kono realizes they are being watched; and McGarrett prepares to take his relationship with Catherine to the next level.

A new episode of "Hawaii Five-0" will be aired 9pm ET on CBS.