Mamir

They use 5 original songs from 5 different artists in their theme songs' line up. https://twitter.com/nd_fujitv/status/1401811205363167235?s=19

I think Fuji prepares this drama to repeat the glory of Code Blue.

Imo, Yell really has set a high standard (rating & story) for asadora in this decade. But still I do hope that the next asadoras will be great too.

Yes! Most of the supporting cast of Yell are actually a singer or musical-actor/actress, like Star Mitarai & Prince Hisashi (they both play as Mozart in Das Musical Mozart Japan), also Todo-sensei (a famous singer), Fujimaru, Chizuko, Yamafuji, Iwaki-san, Shouko-san, Sekiuchi's mom, and some others as cameo.

It still on episode 6 actually. You can check it on their website cause they always update the "pickup songs" after an episode has aired.
https://www.wowow.co.jp/drama/original/coldcase3/pickupsongs/

And it got subbed up to #4 currently by earthcolors on d-addict.
https://www.d-addicts.com/forums/viewtopic.php?t=165498