Up next is "A Burden of Blood" episode of CBS series "Elementary" where Sherlock (Jonny Lee Miller) and Joan (Lucy Liu) will hunt for a copycat killer.

While taking on a homicide case, Sherlock and Joan will discover that the murderer's strategies invites comparison to the tactics of a notorious criminal.

Interestingly, the famed killer remains locked up behind bars, so who could be committing the terrible acts this time?

It looks like the prisoner has attracted a psychopathic fan who is geared on continuing his legacy.

On the other hand, Detective Bell (Jon Michael Hill) is preparing for the police sergeant's exam and Sherlock and Joan, the two best specialist in the Big Apple's police department, are coaching him.

While Joan may be sincere in helping a colleague, Sherlock may simply by aiding Bell so the latter will be promoted and sent somewhere else. Sherlock has been jealous of Bell's closeness to Joan.

In the previous episode, Sherlock investigated the horrid killing of a retired FBI agent. The body was found shredded by a wood chipper. Later on, clues hinted that the attacker is someone familiar to the victim.

The deceased agent's ex-wife disclosed to the investigators that he was working on an unresolved case. The agent was keen on the kidnapping incident of a 10-year old girl who was returned to her parents after a decade.

It looks like the girl was a fraud and she could be the agent's killer.

Sherlock failed to prove that she did the crime so the episode ended without a resolution, reports Christian Today.

Also on the episode, a dark backstory of Joan was revealed. She and her stepfather have a rough relationship, reports International Business Times.

"Elementary" season 4 airs on CBS every Thursday at 10 p.m. EST.