Party of Five to The Flash
5 connections
Party of Five
The X-Files
In the X-Files episode "Milagro" Mulder & Scully visit a graveyard where Party of Five's Diana and Nicholas Salinger are buried.
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