I am looking forward to this.
This article explains the premise a bit but be aware there are some plot elements in the article so if you want to go in blind don’t read.
“The Bones/Sleepy Hollow crossover is like a great episode of The X-Files, where the Bones hour is the Scully, logic-based perspective and the Sleepy Hollow hour is more Fox Mulder-esque,”
Spoilered because it contains some plot elements.
On Bones, “the grisly discovery of human remains lead Brennan (Emily Deschanel) and Booth (David Boreanaz) on a hunt for clues, during which they encounter Ichabod Crane (Tom Mison) and Abbie Mills (Nicole Beharie), searching for answers of their own. Realizing that they are after the same evidence, they team up to solve the mystery. Then, immediately following on Sleepy Hollow, the intrigue continues as Ichabod’s old nemesis is back from the dead. Ichabod and Abbie need advanced forensic help and expertise to stop him and turn to Brennan and Booth to unlock 18th century secrets using 21st century science.”