The Tree Dies Standing (2022)

=> Both dramas depict how the North South Korea divide affects and separates people
---> in CLOY, it's the couples being separated and cannot be physically together for a long time
---> in Curtain Call, the grandma is separated from her first original family from North Korea
=> Female lead is a CEO in both dramas and Choi Dae Hoon is playing the brother of the female leads in both dramas.
=> Though male lead in Curtain Call is South Korean, he is pretending to be a North Korean character so that North Korean aspect of him makes him similar to the North Korean male lead in CLOY. Curtain Call male lead is also an actor and he plays North Korean characters in his plays, one time even mentioning Hyun Bin (CLOY actor)
=> Bonus: Female lead Ha Ji Won once worked with Hyun Bin in Secret Garden

Similar vibes so far. We can expect a melodrama genre from Curtain Call as we also had in Mask.
A person goes into a rich family household to act as someone else.

Both are 20th century historical korean dramas, with a setting/theme of theater as central part of plot.

An person is hired to play the part of a long lost family member to appease a dying family member forms the premise of both stories.