TV EXCLUSIVE: Chris O'Donnell on Why You Don't Mess With LL Cool J: 'He is a Force to Be Reckoned With' By Raphael Chestang 3:54 PM PDT, September 23, 2016 This video is unavailable because we were unable to load a message from our sponsors. If you are using ad-blocking software, please disable it and reload the page. 13:06EXCLUSIVE: Chris O'Donnell on Why You Don't Mess With LL Cool J01:03Biz Markie Dead at 57: Remembering the 'Just a Friend' Singer04:39Chris Pratt on the Secret to His Happy Marriage With Katherine S…01:35See Chris Hemsworth’s Close Encounter With a Wild Shark (Exclusi…14:40Peter Weber on Possible 'Bachelor' Return, Kelly Flanagan Split …08:47Why Jared Haibon Doesn’t Feel Connected to Baby With Ashley Iaco…08:25Jeffree Star on Kanye West Rumors and Why He’s Permanently Movin…00:58On Set of Maddie and Tae’s Music Video for ‘Woman You Got’ (Excl…07:36Jerry O’Connell on Joining 'The Talk' and Anniversary With Rebec…04:34Tyron Woodley on Jake Paul Fight and Training with Floyd Mayweat…07:30Common on ‘Never Have I Ever’ and Finding Love With Tiffany Hadd…01:37Dwayne Johnson Puts on His Chef Hat to Travel the Country With T…01:00JoJo Siwa Goes Head to Head With Charli D'Amelio on 'Celebrity F…15:28‘RHOP’s Wendy Osefo on Her Season 6 Glow-Up and Facing Off With …08:44Joanna and Chip Gaines Want Fans to Fall in Love With New Stars …02:28'Love Island' Sneak Peek: Korey Goes on a Date With Three New Is…02:01'Bringing Up Bates': Travis Serenades Katie During Romantic Marr…01:47'90 Day Fiancé': Andrei and Elizabeth's Sister Becky Get Into an…25:06Revelations From Britney Spears’ Conservatorship Hearing, Justin…03:05How Britney Spears Hopes to Set a Precedent After Feeling 'Manip… Season eight of NCIS: Los Angeles premieres on Sunday, and ET stopped by the set, where star Chris O'Donnell compared it to a family reunion. "The cast especially can, a lot of times, feel like your siblings," O'Donnell says. "There are days that you love each other and days that you hate each other." RELATED: 'NCIS: Los Angeles' Star Daniela Ruah Is Pregnant With Baby No. 2!Siblings are known to have the occasional scuffle, but no matter how much co-star LL Cool J (real name: James Todd Smith) feels like O'Donnell's brother, the two won't be going to toe to toe. "That dude is one of the strongest dudes you can ever run into, as we all know," O'Donnell points out. "Todd is a force to be reckoned with."But is that force strong enough to get O'Donnell to perform on LL's other show, Lip Sync Battle?WATCH: Michael Phelps, Simone Biles and Aly Raisman Make 'Lip Sync Battle's Live All-Star Show a Rio Reunion"I hope to get some of the guys from this show over there at some point," LL tells ET. "That would be a lot of fun."NCIS: Los Angeles returns to CBS on Sunday at 8:30 p.m. ET/PT.EXCLUSIVE: Idina Menzel Reacts to 'Frozen' Campaign for Elsa to Have a Girlfriend at Billboard Music Awards This video is unavailable because we were unable to load a message from our sponsors. If you are using ad-blocking software, please disable it and reload the page.