'Sleepy Hollow' season 4 episode 8 spoilers: Supernatural infection threatens Washington; can Ichabod and the others stop the curse?

Ichabod (Tom Mison) and his friends deal with one of their biggest enemies yet on the upcoming episode of Fox's supernatural drama "Sleepy Hollow" season 4.

Titled "Sick Burn," tonight's episode will feature a supernatural infection that threatens the entire city of Washington. According to the official synopsis, internet sensation Logan Macdonald heads to Washington to visit. A supernatural infection spreads through a viral video upon his arrival, leading Ichabod and Co. to deal with one of their biggest enemies yet: the Internet.

Similar to a "fire-flu," the disease quickly infects anyone who views a particular video. Molly (Oona Yaffe) will also be infected with the supernatural infection, pushing the team to find a cure before it's too late. The hour will also feature Molly as she sees a frightening vision that could predict a dark future for all humanity.

Fox released a new promo clip for the episode, and it shows Ichabod trying to handle the situation. He stands in a public park and calls on the people to keep their hands off of their devices. However, he appears to be doing a terrible job at convincing people not to use their smartphones to prevent the infection from spreading.

"People of Washington, your mobile device is a weapon. Switch them off ... now," he tells people in the area, who looks at him like he has lost his mind. "I could've told you that wasn't gonna work," Diana (Janina Gavankar) tells her partner.

In the previous episode, Molly was celebrating her 11th birthday when she became the victim of a monster that targets Witnesses. It turned out that the creature was a shape-shifter who was just pretending to be Diana's estranged husband. To find Molly, Jenny (Lyndie Greenwood) made a deal with the demon who later left a map with the young girl's location.

The fourth season of "Sleepy Hollow" airs every Friday night at 9 p.m. ET on Fox.