Riot Games released the new cinematic for League of Legends' Season 2024. The new cinematic is called "Still Here" and with its release Season 2024 has officially kicked off.
I assume that this cinematic will also play within League of Legends itself, perhaps when you launch the game. I do not know how these work as I do not play League of Legends. However, if you can't access the game yet or just want to see the cinematic outside...