Jane's (Angie Harmon) undercover skills will be tested in a new case the Boston PD is working on in the upcoming episode of "Rizzoli & Isles."

In the episode titled "2M7258-100," CarterMatt reports that the female detective will voluntarily go to the county jail and pose as one of the convicts there. This is part of the police's sting operation to draw out a criminal who is hiding after committing a brutal murder. Jane will go undercover to try and find out as much as she can about the culprit. She may have to tap her acting ability too, as the inmates are quite sensitive to scams and con people. Jane is putting her life in danger so the faster they apprehend the criminal, the better for her.

This also marks the 100^th episode milestone for the show. According to executive producer Jan Nash, Sharon Gless has agreed to guest star at Harmon's request. The pair accidentally met while eating at a Los Angeles restaurant. Harmon reportedly asked the television icon to join them for the 100^th episode and the latter said yes.

Nash said in a recent interview that Harmon did a great job directing the episode. She also said that viewers could look forward to "some wonderful performances."

As for the series' ending, the EP said everyone has been feeling a bit sad.

In the same interview, Nash says: "It was both a challenge and a joy. I think as sad as we are that it's ending, if it is going to end, we're glad that we get to end it in a way that allows us to take the characters to a place where we would like to leave them. We feel very fortunate that we've gotten that opportunity, but again, it is very sad. We started shooting the final episode last week. It's been very emotional." 

"Rizzoli & Isles" season 7 airs Mondays at 9 p.m. EST on TNT.