Sleepy Hollow to The Flash
7 connections
Sleepy Hollow
Bones
Temperance and Booth from Bones team up with Icabod and Abbie from Sleepy Hollow on a case
CSI: Crime Scene Investigators
An episode of Bones has a reference to a prostitute who worked at the (fictional and from the CSI universe) Tangiers hotel.
The X-Files
Morley cigarettes are smoked by Warrick Brown in a episode of Crime Scene Investigation.
Homicide: Life On The Street
Homicide's John Munch questioned The X-Files' The Lone Gunmen.
Law & Order
Law and Order and Homicide crossed over on four episodes
Arrow
Hudson University is the fictional University where many Law & Order characters graduated as well as the location of F.I.R.E.S.T.O.R.M. On Arrow
The Flash
Arrow spun off The Flash