On last week's episode of "The Mentalist," the team investigated the suspicious death of a high-tech cartographer. 

In "The Golden Hammer," the FBI began investigating the death of Charles Whitaker, a computer engineer who specialized in mapmaking in Houston, Texas. He died from heart failure due to an overdose of illegal drugs. However, Charles had no drug history, and did not have any drugs in his house. 

Jane (Simon Baker), Lisbon (Robin Tunney) and Fisher (Emily Swallow) met Charles' brother at Charles' apartment, and Jane finds a newspaper that has some letters curiously circled. Meanwhile, Lisbon and Fisher check out Charles' company, and Lisbon gets a call from Osvaldo Ardiles (David Norona), who used to work for the D.A.'s office in Sacramento and was invovled in the CBI's investigations. He asks her out to dinner to discuss business. 

After speaking to people at Charles' company, Lisbon and Fisher begin to think that Charles was worried that classified data had been stolen from inside the company. Jane decides that there is a coded message hidden in the newspaper, but he can't yet figure it out. Jane begins to think that Charles found a spy in his company. 

Jane finds out that Charles found the newspaper in a nearby park, so he decides to go the park the next day. He leaves the paper on a bench to see who will pick it up. A man comes to the park and takes the paper. The FBI later finds out that the person is buying secret data from inside the company Charles worked for. However, Jane does not believe that the man or the man's client killed Charles. 

Lisbon then meets Ardiles at dinner, and he tells her that he has the feeling that his phone has been hacked and someone is spying on him. He also has the feeling that somebody is following him. 

Later, the FBI creates a setup to entrap the killer. They arrest Charles' brother to make the killer believe that he or she is safe to sell more secret data. 

Jane, Lisbon and Cho (Tim Kang) wait for the data seller to show up. Avery Schultz, the CEO's secretary, finally shows. The team arrests her, and she confesses, saying she killed Charles because he found out what she was doing inside the company. 

Meanwhile, Rigsby (Owain Yeoman) and Van Pelt (Amanda Righetti), who now work in digital security, are trying to find out who bugged Ardiles' phone. They locate Ardiles via his cellphone, and go the location. But when they get there, they find that he's dead.

Van Pelt then searches on Ardiles' phone, and finds that there are twelve encrypted files with twelve names of people who used to work for the CBI, including Jane, Lisbon, Cho, Rigsby and Van Pelt. It turns out the entire former CBI team has been bugged. 

The next episode, "Black Helicopters," will not air until March 9. 

While spoilers are not yet out for the next episode, TVLine reported that Lisbon will be getting a new beau in the form of an FBI Special Agent. 

FBI Special Agent Marcus Pike, who debuts in episode 16, is described as "a charming man with integrity, a blue collar cop with FBI smarts." He will be instantly drawn to Lisbon when he helps Lisbon and Jane track a band of art thieves. He will be around for at least five episodes. 

The next episode airs Sunday, March 9 at 10 p.m. on CBS.