Which Are the Largest Current Shared Universes in Primetime TV?

'NCIS' Crossover, 'The Walking Dead,' 'Law & Order: Organized Crime'
Sonja Flemming/CBS; Jackson Lee Davis/AMC; Eric Liebowitz/NBC

If you’re a TV fan, there is plenty to watch right now. And if you’re a fan of crossovers — even minor ones with a character or for an episode — you’re also in luck. Primetime television has been filled with shared universes, especially in recent years.

If you’re into procedurals (like the NCISes — which united for a three-show crossover — or Dick Wolf‘s extended universe), zombies (The Walking Dead universe), or superheroes (the Arrowverse), you’re covered. In fact, crossovers aren’t necessarily beholden to a network: Chicago P.D.‘s (NBC) Tracy Spiridakos went over to FBI (CBS).

So scroll down as we examine the shared universes currently part of primetime television. (Notes: We’re only including shows that have aired, have premiere dates, or have been ordered to series, not any in development.)

Grey's Anatomy Station 19 Crossover Finale 2020 Andy Meredith
ABC/Kelsey McNeal

Grey's Anatomy

Number of shows: 3

Grey’s Anatomy (2005-present), Station 19 (2018-present), Private Practice (2007-2013)

FBI Most Wanted Crossover
Mark Schafer /CBS


Number of shows: 3

FBI (2018-present), FBI: Most Wanted (2020-present), FBI: International (2021-present)

One Chicago

One Chicago

Number of shows: 4

Chicago Fire (2012-present), Chicago P.D. (2014-present), Chicago Med (2015-present), Chicago Justice (2017)

Arrowverse Crisis on Infinite Earths Crossover - Melissa Benoist as Kara/Supergirl, Brandon Routh as Ray Palmer/Atom, Stephen Amell as Oliver Queen/Green Arrow, Ruby Rose as Kate Kane/Batwoman, Chyler Leigh as Alex Danvers, Grant Gustin as The Flash, David Harewood as Hank Henshaw/J'onn J'onzz, Jesse Rath as Brainiac-5, Audrey Marie Anderson as Harbinger, Katherine McNamara as Mia, Caity Lotz as Sara Lance/White Canary, Tyler Hoechlin as Clark Kent/Superman and Bitsie Tulloch as Lois Lane
Katie Yu/The CW


Number of shows: 6

The Flash (2014-2023), DC’s Legends of Tomorrow (2016-2022), Batwoman (2019-2022), Supergirl (2015-2021), Black Lightning (2018-2021), Arrow (2012-2020)

(Note: Yes, “Crisis on Infinite Earths” brought in a few more shows, like Lucifer and Smallville, to the mix, but we’re not including cameos.)

Norman Reedus as Daryl Dixon, Andrew Lincoln as Rick Grimes, Danai Gurira as Michonne - The Walking Dead - Season 9, Episode 1
Jackson Lee Davis/AMC

The Walking Dead Universe

Number of shows: 7

The Walking Dead: Dead City (2023-present), The Walking Dead: Daryl Dixon (2023-present), The Walking Dead: The Ones Who Live (2024-present),Fear the Walking Dead (2015-2023), The Walking Dead (2010-2022), The Walking Dead: World Beyond (2020-2021), Tales of the Walking Dead (2022)

Christopher Meloni as Detective Elliot Stabler, Mariska Hargitay as Captain Olivia Benson in Law & Order: Organized Crime
Eric Liebowitz/NBC

Law & Order

Number of shows: 7

Law & Order: Special Victims Unit (1999-present), Law & Order: Organized Crime (2021-present), Law & Order (1990-2010, 2022-present), Law & Order: True Crime (2017), Law & Order: LA (2010-2011), Law & Order: Criminal Intent (2001-2011), Law & Order: Trial by Jury (2005-2006)

Brian Dietzen, Chris O'Donnell, Vanessa Lachey, Wilmer Valderrama, Gary Cole, Katrina Law, Sean Murray, Noah Mills, and LL Cool J — 'NCIS' Crossover
Sonja Flemming/CBS


Number of shows: 8

NCIS (2003-present), NCIS: Hawai’i (2021-present), NCIS: Sydney (2023-present), NCIS: Origins (2024/2025 season), Untitled NCIS Tony/Ziva spinoff (TBA), NCIS: Los Angeles (2009-2023), NCIS: New Orleans (2014-2021), JAG (1995-2005)

NCIS Los Angeles Hawaii Five-0 Crossover
Richard Cartwright/CBS

CBS Procedurals

Number of shows: 12

NCIS (2003-present), NCIS: Hawai’i (2021-present), NCIS: Sydney (2023-present), NCIS: Origins (2024/2025 season), Untitled NCIS Tony/Ziva spinoff (TBA), NCIS: Los Angeles (2009-2023), Magnum P.I. (2018-2024), MacGyver (2016-2021), NCIS: New Orleans (2014-2021), Hawaii Five-0 (2010-2020), Scorpion (2014-2018), JAG (1995-2005)

Law & Order SVU - Mariska Hargitay - Season 21 - Olivia Benson
Virginia Sherwood/NBC

Dick Wolf

Number of shows: 18

Law & Order: Special Victims Unit (1999-present), Chicago Fire (2012-present), Chicago P.D. (2014-present), Chicago Med (2015-present), FBI (2018-present), FBI: Most Wanted (2020-present), Law & Order: Organized Crime (2021-present), FBI: International (2021-present), Law & Order (1990-2010, 2022-present), Law & Order: True Crime (2017), Chicago Justice (2017), In Plain Sight (2008-2012), Law & Order: LA (2010-2011), Law & Order: Criminal Intent (2001-2011), Conviction (2006), Law & Order: Trial by Jury (2005-2006), Homicide: Life on the Street (1993-1999), New York Undercover (1994-1999)