While the mystery of the Chess-Piece Killer remains unsolved, a new profiler from the FBI will join McGarrett (Alex O'Loughlin) and the team in the third episode of "Hawaii Five-0" season 7.

The team just returned from their successful mission in Europe in the previous episode. But before they tracked down a former M16 agent who went rogue, McGarrett and Danny (Scott Caan) tried to seek the help of FBI profiler Alicia Brown (Claire Forlani) to identify the person responsible for the deaths of serial killers in Hawaii. Although, Brown was reluctant to get involved with the case.

However, in the episode titled "He Moho Hou (New Player)," Brown might be left with no choice but to work with the Five-0 team to finally stop the mysterious vigilante from causing more deaths.

The synopsis for the upcoming episode posted on The Futon Critic reads: "When FBI Profiler Alicia Brown finds a body in her bed, she is forced to join McGarrett in the hunt for the chess-piece killer. Also, Kono (Grace Park) reconnects with a former surfing competitor (Kanya Sesser), who is now a disabled and homeless war vet."

Sesser is best known as the lingerie model with no legs. This will be her second TV break after appearing in CBS's medical drama "Code Black" in 2015.

Meanwhile, executive producer Peter M. Lenkov told Entertainment Weekly that McGarrett's love interest, Catherine (Michelle Borth), will return in the 150th episode of "Hawaii Five-0." But it does not mean that the two will get back together. "I think people are interpreting it like it's her coming back into the relationship and starting all over again, but I just don't think that can happen after all that these two have gone through," Lenkov said. "Her relation to the story is more plot-driven than reigniting that relationship," he went on to say.

"Hawaii Five-0" season 7 episode 3 is scheduled to air on Friday, Oct. 7, at 9 p.m. ET on CBS.