Horror comedy reigns supreme in Indian cinema at the moment, so it was probably inevitable that 2005's Chandramukhi was going to get a sequel. And that is exactly what happened; Chandramukhi 2 (2023) shares a number of plot elements with the earlier film, including an ancestral curse, a broken family, a clever outsider charged with solving everyone's problems, and of course the Room Which Must Never Be Opened. In this case, though, it's the same Room Which Must never be Opened, because Chandramukhi 2 is a direct sequel to the earlier movie.
Wealthy matriarch Ranganayaki (Radhika Sarathkumar) and her family have faced a series of disasters in recent years, including the family factory burning down and a car accident which put younger daughter Divya (Lakshmi Menon) in a wheelchair. The family's Guru (Rao Ramesh) suggests that the family have neglected their ancestral deity, and the solution is for the family to gather in Vettaiyapuram and perform prayer sin the ancestral temple. This will require the entire family, including the two orphaned children of the daughter who ran away to marry a man "from a different religion," as the subtitles delicately put it. The daughter and her husband died in a plane crash years ago, and the family have made no effort to contact the children (Manasvi Kottachi and Sanjiv V) but now they are needed.
The children are introduced on a school bus which has been taken hostage by a band of violent and well-armed thugs. Fortunately, the kids have a protector, their guardian Pandian (Raghava Lawrence), who arrives and defeats the bad guys in spectacular fashion, because while Superstar Rajnikanth doesn't return for the sequel, this is still very much a Rajnikanth movie.
Ranganayaki rents a castle near the temple from Murugesan (Vadivelu), who was comic relief in the first movie and continues to be comic relief here, and the family movies in, bringing the children and Pandian along with them. And then the movie focuses on family drama for a while, as Ranganayaki learns to stop being a jerk and accept the kids, while Pandian makes a connection with Lakshmi (mahima Nambiar), beautiful daughter of the groundskeeper.
Lakshmi has always wanted to explore the palace, and late at night Pandian helps her sneak in. They explore the forbidden south wing, and Lakshmi discovers The Door That Must Never Be Opened, though she does not open it at this time. Still, the genre shifts at this point. The family temple is overgrown and needs to be cleaned before the rituals can be performed, though the temple's priest (Y. G. Mahendran) warns them that that will release a dangerous spirit. They hire workers from outside the area, but after a pair of tragic deaths the workers leave, and so Pandian clears the temple himself, starting a fire in the process. He's met by a mysterious sage (so mysterious that I don't know who played him) and learns that the angry ghost of Chandramukhi (Kangana Renaut) has possessed one of the women in the household.
The possession in the previous movie was ambiguous, but probably psychological rather than supernatural. This time it is definitely the ghost of slain dancer Chandramukhi, who is definitely here to take her revenge on Vettaiyan (Raghava Lawrence), who murdered the man she loved and then ordered her burned alive, though the backstory from the first movie is needlessly expanded and we learn that Vettaiyan is actually a general named Sengottaiyan, who murdered the actual king (Shatru) and Dread Pirate Robertsed himself onto the throne in an effort to possess Chandramukhi.
Despite that twist and the added supernatural elements, though, this is basically the same plot as in the first movie, and plays out in much the same way; the giant snake from the first movie appears and does nothing again, and they even use the same trick to convince Chandramukhi to leave. Everything is bigger, though - the special effects are flashier, the scenes set in Chandramukhi's time feature fight choreography lifted from Bahubali, Chandramukhi gets a dramatic sword fight after her big dance scene, and there are actually two ghosts, both of which are real.
Well, almost everything is bigger. There is nothing in this movie to match Jyothika's magnetic performance in the original, and while Raghava Lawrence is doing a very good Rajnikanth impression, he's still not Rajnikanth. The scale is bigger, but the ambiguity that made the first movie work is completely gone, leaving us with a very by-the-numbers haunted house movie and broad comedy scenes that just keep going and going. This is skippable - you're better off watching the Bhool Bhulaiyaa sequels, which at least mix up the plot a bit.