Benson to Hawaii Five-O
16 connections
Benson
Soap
Soap's Benson DuBois spunoff on to his own show, Benson
Hanging In
Maggie Gallagher from Hanging In crossed over onto Soap
Maude
Hanging In (and Maude's) Maggie Gallagher crossed over onto Soap for 10 episode
All in the Family
The first All in the Family spinoff character was Maude. Maude was Edith Bunker's cousin.
The Jeffersons
The Jeffersons' George Jefferson was the second All in the Family supporting character to spinoff onto his own show.
Mission: Impossible (1966)
George Jefferson gets help from Barney Collier from Mission Impossible
Mission: Impossible (1988)
Mission: Impossible was continued 22 years later
Diagnosis: Murder
Diagnosis Murder's Doctor Jesse Travis's father is a spy that someone is trying to kill. One of the possible suspects is the original Mission: Impossible's Cinnamon Carter.
Lost
The airplane that crashed and strand the cast of Lost was Oceanic Airlines Flight 815 also featured on Diagnosis Murder.
Veronica Mars
In an episode of Veronica Mars, Veronica's fortune cookie had the numbers that won Hurley from Lost the lottery.
The X-Files
The mugshot of Malcolm T Wiggins from the X-Files episode "Titonus" appears on the wall of a police interrogation room in the Veronica Mars episode "Leave it to Beaver." Also the fictional car rental company Lariat where Mulder & Scully always rented their cars was featured prominently on the Veronica Mars episode "Rat Saw God."
Homicide: Life On The Street
Homicide's John Munch questioned The X-Files' The Lone Gunmen.
Law & Order: Special Victims Unit
John Munch was a detective Homicide and then SVU
Murder, She Wrote
Jessica Fletcher taught criminology at Hudson University, where various Law & Order characters attended
Magnum P.I.
Murder, She Wrote had a two episode crossover with Magnum P.I.
Hawaii Five-O
Magnum impersonates McGarrett of Five-O on the police radio