Fans of NCIS are in for a big change when the series returns for its 19th season later this year.
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After 18 years of holding down CBS's 8pm Tuesday slot, the hit series is relocating to Mondays, where it will air at the new time of 9pm and lead into new spin-off NCIS: Hawai'i.
The announcement comes just weeks after it was confirmed that Mark Harmon, who has played Special Agent Jethro Leroy Gibbs since season one, will reprise his role on the show despite rumours to the contrary.
WATCH: See the first trailer for new spin-off NCIS: Hawai'i
According to Variety, the decision to move the long-running series from the time slot it has held for almost twenty years was made to allow the network to rebrand Tuesdays as an all-FBI night. As such, starting from this September main series FBI will air at 8pm, followed by newcomer FBI: International at 9pm, with FBI: Most Wanted closing out the night at 10pm.
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Likewise, NCIS and new series NCIS: Hawai'i will make Mondays the channel's NCIS night (even though NCIS: Los Angeles will will continue to air at 9pm on Sundays).
The decision to dedicate entire nights to just one franchise is not unprecedented. For the last couple of years, the shows of One Chicago - Chicago Fire, Chicago PD and Chicago Med - have been dominating NBC's Wednesday night schedule with all three hours of evening primetime occupied by the shows.
NCIS will air on Mondays when it returns for season 19 in September
According to Cinema Blend, since making the move "the numbers of all three series experienced a boost and have remained generally consistent".
It seems that CBS is hoping to replicate the success, with network boss Kelly Kahl telling Variety: "If you look at the proof of what does work, these franchises work. And they work on a multitude of levels. They generally get pretty darn good live ratings, they get good delayed viewing, and they stream pretty well. That's a win-win-win."
Vanessa Lachey will lead new spin-off NCIS: Hawai'i
This year has seen several major changes to the NCIS franchise. While it was announced in February that NCIS: New Orleans would end with its current season, new series NCIS: Hawai'i will be the first with a woman at the helm - and the first set outside mainland USA.
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It's been confirmed that actress and TV presenter Vanessa Lachey will take on the role of Jane Tennant, a female officer who has rised through the ranks to become the first female Special Agent in Charge of NCIS Pearl Harbor
Sharing the exciting news of her casting to Instagram, Vanessa wrote: "Honored is an understatement! To join the NCIS franchise as the first female lead and to do it on the Beautiful Islands of Hawai'i... I still can't believe it! Thank You CBS for believing in me! Now let's get to work!"
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