Both have a story within a story/framing device plots in which either two MLs or two FLs are involved in the lives of strangers who come to them for issues in their lives.

Both are about a group of people, mostly students, who find themselves in a seemingly supernatural building they must try to escape from.

While one is historical and the other modern day, both have a similar concept of the ML having two different personalities - one cold and traumatized and the other stronger and warmer in his love for the FL. Both dramas have a love triangle between the personalities and the FL, with her more drawn to the cold one who assumes she likes the other personality better.

Both are Chinese fantasy/historical movies with a similar style and vibe, as well as extensive CGI/special effects.

Both have the same setting, very similar plot and characters, and focus on the same events. Both also have the same style.

Both MLs are almost supernaturally unlucky, causing them to constantly get into trouble. The other lead is very lucky.

Both are mini dramas in which the lead has an unusually high sense of smell which they use to solve unusual murder mysteries.

Both are Republican Era mini dramas set in a town where murders and wrongful deaths have taken place, with a policeman ML and smart FL trying to solve the cases.

Both are mini dramas in which the FLs enter a game world and fall in love with the main character.
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Both FLs are in a VR world of romance (script vs. game) in which they have to fix the story and in the process fall in love with the domineering CEO ML.

Both are historical Chinese movies focusing on a love story between the emperor and a man who he meets and saves.

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