Season 4 ends with Holmes and Watson facing reprisal from the perpetrator who wants Morland dead, and realizing they dangerously underestimated the scope of their new enemy's influence.
Holmes and Watson discover the perpetrator behind the attempt made on Morland's life and find a shocking connection to themselves.
Holmes suspects his father of murder after one of Morland's employees is killed under the guise of a robbery.
Holmes and Watson investigate a double homicide and discover the victims were staging a fake murder at the moment they were killed. Meanwhile, Joan's inside man at Morland's office encounters a problem that threatens to expose her spying to Holmes and his father.moreless
Holmes and Watson investigate the murder of a man who secretly fought crime dressed as a comic book superhero. Meanwhile, Morland makes a surprise donation to Watson's favorite charity, in order to compel her to do him a business-related favor.moreless
The identity of Sherlock's mother is revealed and his strained relationship with Morland reaches a breaking point. Meanwhile, an elderly woman emerges as the prime suspect in the murders of three gang members.moreless
Holmes' relationship with his father suffers a setback when he discovers Morland has been keeping a secret that threatens their safety. Meanwhile, Sherlock and Watson investigate two murders linked to a college and its illegal recruitment practices.moreless
Holmes and Watson hunt for a computer hacker responsible for three murders, including the death of a Russian billionaire who was visiting New York City. Meanwhile, Joan receives a solo dinner invitation from Sherlock's father.moreless
Morland offers to act as one of Sherlock's "Irregular" consultants to help his son and Joan solve a case.
Sherlock offers to help his father resolve a work issue in exchange for his prompt departure from New York City. Meanwhile, Holmes and Watson investigate the murders of two men who looked alike. The probe leads them into the world of facial recognition technology.moreless
Morland offers to use his influence to have Sherlock and Joan reinstated as consultants to the NYPD, but Sherlock questions his father's motive. Meanwhile, Watson helps the FBI investigate a triple homicide at a top secret research lab.moreless
Season 4 begins with Holmes facing criminal charges in the aftermath of his recent violent behavior and relapse, and his father arriving in New York to fix his estranged son's troubles by any means necessary. Meanwhile, Sherlock and Watson investigate a case in which a woman goes missing and may have been killed by her husband.moreless
Trapped in the past, Abbie tries to convince Ichabod that they are future partners while trying to stop Katrina from assuring the Horseman's victory.
Ichabod and Abbie try to stop Henry's scheme to use a mystic bell to create a new cult of witches. However, they learn that he has an unexpected ally. Meanwhile, Irving comes after Jenny.moreless
Ichabod and Abbie find a new series of tunnels beneath Sleepy Hollow and have an encounter with an old friend of Ichabod's. Meanwhile, Katrina receives a visit from Henry, and Jenny receives a visit from Irving.moreless
Solomon Kent, a warlock who set off the Salem Witch Trials to protect himself, seeks out a Grimoire that will give him the power to undo the mistake in his past that turned him into a warlock. Meanwhile, Irving approaches Abbie, while Henry contemplates his past and decides on his future.moreless
The End of Days draws nigh, and Ichabod and Abbie capture Abraham in the hopes of learning where they can find Moloch and Henry. However, Abraham reveals that the Sword of Methuselah can only be used at a terrible cost.moreless
Ichabod and Abbie discover the existence of the Sword of Methuselah, the only weapon capable of killing Moloch. They race to find it, only to discover that Henry has learned of the weapon's existence and sent the Horseman of Death to get it first.moreless
Abbie and Jenny investigate strange suicides at Tarrytown that may be connected to their mother Lori. Meanwhile, Katrina realizes the nature of the baby and prepares to banish it back to Purgatory.
Ichabod and Abbie join forces with Katrina to take on a succubus that Henry has sent out to drain the life force from her victims, killing them.
Henry brings in a doctor to monitor Katrina's condition after her sudden illness. She manages to escape and Ichabod finds her, and they realize that Moloch has a new plan to manifest on Earth. To stop him, Ichabod reaches out to Henry to use his powers to save his mother.moreless
Corbin's son Joe returns from overseas after receiving an honorable discharge after his platoon is wiped out in a bizarre attack. Ichabod and Abbie soon realize that something is wrong with him. Meanwhile, Henry tells Irving that there is a way for him to free his soul, but it has a cost that Irving may not want to pay.moreless
A ghostly spirit, the Weeping Lady, kills Ichabod's friend Caroline. After it attacks Abbie, Ichabod realizes that the ghost is going after his loved ones... and Katrina is her next intended victim.
When a child in Sleepy Hollow goes missing, Ichabod and Abbie realize that a Pied Piper-like creature that serves Moloch is responsible.
Ichabod and Abbie discover that Henry is trying to spread a curse of violence, unleashing the darkness in individuals so that they kill. Meanwhile, Jenny discovers who was responsible for her mother's imprisonment at Terrytown, and Frank learns the truth about his lawyer.moreless
To defeat the Horseman, Ichabod and Abbie seek out a patchwork man that Franklin and the Sisterhood built to oppose Moloch's servants. Meanwhile, the new sheriff arrests Jenny and Frank explains that demons killed his supposed murder victims.moreless
With Ichabod buried alive and Abbie trapped in Purgatory, Ichabod's son, the Horseman of War, has free reign over Sleepy Hollow... and soon, the world.
While Captain Irving faces the ultimate test of his loyalty, Ichabod and Abbie find a secret passage within Washington's Bible that reveals the truth about the First President's death.
The two worlds collide as Sleepy Hollow is rocked to its core in the final battle between Good and Evil.
While attempting to communicate with Katrina in Purgatory, Ichabod and Henry Parrish unwittingly unleash a new evil.