"Elementary's" recent cases-of-the-week seem to be portents of Morland's mysterious plans being set in motion. But will the detectives' newest case prove that Morland is the monster or that he is the victim?

The previous episode saw Sherlock Holmes (Jonny Lee Miller) and Joan Watson (Lucy Liu) busy with a carjacking that turned out to be staged, in order to cover up a murder. Joan's double agent reached out to her and informed her that Morland (John Noble) discovered they were spying on him. There might be some truth to that as the elder Holmes made a surprise visit to the brownstone.

Sherlock's new case might have some surprising ties to his father. In episode 22 of "Elementary" season 4, Sherlock and Joan will look into a robbery gone bad. Sherlock's father will become their prime suspect when one of the victims turns out to be an employee of Morland.

A short clip for the upcoming episode, "Turn It Upside Down," teases another contentious meeting between the two Holmes men. The clip starts with Sherlock introducing himself as the son of Morland Holmes, while his father is introduced as a complicated man. Morland tells his son that Sherlock needed to see him as a villain. This is followed by a shot of Sherlock and Joan arriving at a crime scene, with Watson telling her partner that this was an assassination. The truncated clip ends with Sherlock warning his father that he will find out who's responsible for the murder and that he will see to it that they pay.

Sherlock's father previously claimed earlier in the season that he wanted to reconnect with his son, a move that neither Sherlock nor Joan totally believed. And with Joan's spy seemingly murdered, it does raise the question as to why he was killed. Did Morland have him killed?

The show is gearing up for the end of its fourth season, and based on reports, a new face connected to an important person from Sherlock's past is set to appear. According to a TV Line report, "Defiance" alum Tony Curran has been tapped to play Joshua Vikner, an economics professor with ties to Jamie Moriarty (Natalie Dormer). The Scottish actor will be seen in the last two episodes of the season and will also reportedly play a significant role in Sherlock's future.

Episode 22 of "Elementary" season 4 is set to be aired on Apr. 24 at 10 p.m. on CBS.