‘Elementary’ cast
Sherlock (Jonny Lee Miller) grows frustrated with the length of his cognitive recovery as he, Joan (Lucy Liu), and the NYPD investigate a murder that took place during a reenactment of the Revolutionary War in Season 6, episode 3 of CBS’ “Elementary.” CBS

Sherlock and Joan dive into the world of rare antiquities in tonight’s episode of “Elementary.”

According to the synopsis for Season 6, episode 3 of the CBS series, Sherlock (Jonny Lee Miller) and Joan (Lucy Liu) investigate a case in which the victim was killed during a reenactment of the Revolutionary War.

In a sneak peek from the hour, Sherlock tells Joan what he finds out after reading the victim’s emails from his friends.

“I just finished going through the threats made against Mr. [George] Nix (Robert Vincent Smith). And it’s not winning any popularity contests,” Sherlock says of the motive behind the victim’s death. “Half of his friends truly loathe him but I don’t think any of them are the architects of his demise.”

When Joan asks why he thinks that’s the case, the British sleuth explains, “This crime is planned well in advance. Our killer is patient and exact. These are not traits that spring to mind when you read emails like, ‘I’m serious, bro. I’ll beat your butt til you see the stars in the daytime.’”

“Even if these delightful epistolarians did harbor homicidal tendencies, it seems unlikely that any of them would know that Mr. Nix planned to travel back 1776 yesterday and make himself such a ripe target,” Sherlock continues.

Fortunately, going through George’s emails isn’t a waste of Sherlock’s time, as the latter discovers that there’s some sort of rift between the victim and his daughter Marcy (Gia Crovatin).

After Joan takes a look at the exchange of emails between George and Marcy, the former surgeon comments, “It’s nasty stuff. It sounds like Thanksgiving at the Nix’s house would be much fun.”

While the partners have a lead in the investigation, solving the case won’t be easy for them as Sherlock continues to struggle with post-concussion syndrome. “My symptoms are getting worse,” Sherlock says in the trailer for the episode. “They’re interfering with my focus, my sleep, my existence.”

As Holmes grows frustrated with the length of his cognitive recovery, he, according to the synopsis for the hour, finds solace in his growing friendship with Michael (Desmond Harrington).

“Elementary” Season 6, episode 3, titled “Pushing Buttons,” airs tonight at 10 p.m. EDT on CBS.