NCIS: Hawai'i is the fourth and latest installment in CBS' NCIS franchise — and with it comes a new character that breaks the shared universe between NCIS and Hawaii Five-0. The shared universe was established in a two-part crossover event in 2012, but the two universes will, unfortunately, be untethered in an upcoming NCIS: Hawai'i episode. Here's how the inclusion of one new character breaks down the shared NCIS/Hawaii Five-0 universe.
NCIS: Hawai'i and Hawaii Five-0 both focus on solving crimes in the beautiful Aloha State, so a crossover between the two series may seem natural — however, it was NCIS: Los Angeles that established the shared universe between the two franchises. In the first episode of the event, Hawaii Five-0 season 2 episode 21 "Pa Make Loa," Special Agents G. Callen (Chris O'Donnell) and Sam Hanna (LL Cool J) are sent to Hawai'i from the NCIS Los Angeles office to help solve a murder and prevent a biological attack. When the case sent the pair back to Los Angeles in NCIS: LA season 3 episode 21, "Touch of Death," Detective Sergeant Danny Williams (Scott Caan) and Detective Lieutenant Chin Ho Kelly (Daniel Dae Kim) return with them to finish the case once and for all.
Beulah Koale has been cast to appear in an upcoming NCIS: Hawai'i episode, "Spies, Part " — which was directed by LeVar Burton — as New Zealand intelligence officer, David Sola. This, however, raises a problem, as Beulah Koale also portrayed Junior Reigns, a former Navy SEAL and new recruit to the Hawai'i Five-0 Taskforce, on Hawaii Five-0. Having the same actor portray two different characters in the same shared universe would, unfortunately, create some logistical issues that would be difficult to overcome for the sake of another fun crossover event, though not impossible. Koale's appearance as David Sola is a good indicator that NCIS: Hawai'i and Hawaii Five-0 no longer exist within the same universe.
However, it wouldn't be the first time one actor played multiple roles in the NCIS franchise. Many actors, like Sean Harmon and Patrick St. Esprit, have appeared across the NCIS universe as multiple characters. While some have crossed over to different spin-offs after their characters' death, others have co-existed on multiple series while their characters were still alive. With this in mind, a Hawaii Five-0/NCIS: Hawai'i crossover isn't entirely out of the realm of possibility. David Sola doesn't seem to be a major, recurring character, so ignoring this small conflict in lieu of a fun crossover event — even if the conflict makes it non-canon — is certainly still possible.
While a Hawaii Five-0 crossover is still in the air, the new series has plenty of other opportunities for crossovers in the future. A crossover for NCIS and NCIS: Hawai'i is set to air in March, and there are plenty of other opportunities for future connections between the NCIS universes. Whether the shared universe between Hawaii Five-0 and NCIS remains broken or this discrepancy is ignored for future crossovers, there is more than enough NCIS universe for NCIS: Hawai'i to explore.