The person behind the attacks on Morland (John Noble) will finally be exposed in an upcoming episode of the CBS series "Elementary."

In "The Invisible Hand," TV Guide reports that it is time for the big reveal on who wanted the older Holmes dead. Viewers will remember that Morland arrived in New York, claiming he wanted to reconnect with his estranged son. He and Sherlock (Jonny Lee Miller) have had a rough relationship ever since he bailed out on his family. The consultant has yet to forgive his father for leaving them and for the death of his mother.

Sherlock's hatred was further exacerbated when he learned that Morland went to see him not to make amends, but for protection. Someone wanted him dead and he believed Sherlock could help him find out who. A previous investigation revealed that a woman friend of Morland was already killed while out on a trip with him. Morland's fear for his own life pushed him to travel and see his son, even if it meant a lot of chastisement.

Sherlock and Joan (Lucy Liu) have been working hard and trying to learn the identity of Morland's supposed executioner. This time, the truth will finally be revealed, but it will not cause them some breathing space. They will find out that the mastermind has a connection to both of them. Who is the person behind the attacks and how is he related to Sherlock and Joan?

Meanwhile, Miller talked about his character and Liu's dynamics in the series with the New York Post in January. According to him, he was aware of the fans' wish to see Sherlock and Joan in a romantic relationship. The actor said, however, that it was highly unlikely that the two would fall in love. He shared that unless something major happened and turned the ship upside-down, the main characters would remain friends.

"I think we're all on the same page here as far as that goes. Holmes and Watson's relationship is sacred, and if you change that, then the show is not about Holmes and Watson anymore. There are some things you can play with it and some you can't. The fact that one's a man and one's a woman is irrelevant; it's who they are as people that's important," he said.

"Elementary" season 4 episode 23 airs Sunday, May 1 at 10 p.m. EDT on CBS.