Lucy Liu as Joan Watson
Joan’s (Lucy Liu) half-sister Lin (Samantha Quan) suspects that Shinwell is talking to a gang member in a sneak peek for Season 5, episode 7 of “Elementary.” CBS

Joan (Lucy Liu) is worried that Shinwell (Nelsan Ellis) is being drawn back to his past life as a criminal.

In a sneak peek for Season 5, episode 7 of “Elementary,” Lin (Samantha Quan) tells Joan that she thinks she saw Shinwell talking to a gang member.

“I saw him the other day outside of his building [after] I had a meeting with the owners,” the real estate agent tells her half-sister. “Before I got into my taxi, this car pulled out next to him. The guy who got out [appears to be a member of a gang]. Look like Shinwell knew him but didn’t want to talk to him or at least didn’t want to be seen with talking to him.”

“If Shinwell gets caught talking to a member of his old gang, that’s a parole violation,” Joan responds. “If that man is from a rival gang …”

“Then that’s even worse, right?” Lin says, completing Joan’s sentence.

According to the synopsis for the episode, Joan takes “drastic measures” to make sure that Shinwell stays on the right track as he transitions from prison life back to the outside world.

For those who haven't caught up with “Elementary,” Sherlock (Jonny Lee Miller) convinced Joan to assist Shinwell in his re-entry to society, giving her an opportunity to do the kind of helping she did when was still working as a surgeon.

However, in an interview with Entertainment Weekly last September, series executive producer Rob Doherty revealed that “there may be a difference of opinion” between Sherlock and Joan in the future over whether keeping Shinwell in their orbit is a good idea.

Also in the upcoming episode, Joan and Sherlock search for two murderers after a base jumper is shot out of the sky by one killer, and has his parachute sabotaged by another.

“Elementary” Season 5, episode 7, titled “Bang Bang Shoot Chute,” airs on Sunday Nov. 20, at 10:30 p.m. EST on CBS.