Dhayanandam is a story set in a secluded island where an affluent old man named Dhayanandam, portrayed by <actor/v-s-raghavan>, resides in his solitary home with his mentally-ill wife Ponni, played by <actor/kalpana>, and a few loyal servants. His life takes a grim turn when his doctor, <actor/s-n-lakshmi>, reveals that Dhayanandam’s cancer has advanced beyond treatment and he has only a few days left to live. Wishing to ensure his loved ones are present during his final moments, Dhayanandam arranges for all his siblings to come and stay with him. Despite past grievances and his deep-seated anger towards them—particularly because he married Ponni, a woman from a lower caste—he still allows his relatives to be with him, although he harbors resentments due to his belief that they are responsible for Ponni’s mental illness.
Over the next few days, a series of mysterious murders shakes the household. One after another, Dhayanandam’s relatives are killed, sparking suspicion and fear among the remaining guests. The household becomes isolated, with no means of contact with the outside world, heightening the sense of dread. The guests quickly turn on Ponni, Dhayanandam, and their trusted physician, demanding they leave, but Dhayanandam insists they cannot leave without his approval and commands everyone to stay until the culprit is apprehended. Meanwhile, Saravanan, the doctor, advises Dhayanandam to distribute his wealth among his siblings. However, Dhayanandam refuses to do so, insisting that the killer must first be caught before any decisions about his estate are made.
A pivotal character is <actor/vijayan-k>, who plays Jambu, Dhayanandam’s youngest brother. Jambu is depicted as a war veteran who, in reality, has lost both his legs and eyesight in military service. Dhayanandam and Ponni develop a special affinity for Jambu’s son, Ragini, portrayed by <actor/s-r-janaki>. Dhayanandam grants Jambu permission to leave the island, but Jambu chooses to stay. That night, Ragini witnesses a chilling event—she sees a figure resembling Dr. Saravanan, from behind, pushing her father Jambu in a wheelchair down the stairs. Jambu survives, prompting Ragini to accuse Dr. Saravanan, though everyone else—including Jambu himself—believes the assailant must have been someone else wearing a similar disguise.
Tragedy strikes again when Ponni is pushed from the rooftop and killed, intensifying the household’s chaos. Grief-stricken, Dhayanandam declares he will distribute his wealth to Ragini, who has been like a daughter to him. During a tense moment, Ragini plays the piano to soothe Dhayanandam. As she does, a masked figure dressed as Dr. Saravanan suddenly attempts to stab her from behind. In a dramatic act, Dhayanandam shoots and kills the attacker. Just as relief begins to set in, the unexpected appears—the doctor himself appears at the top of the stairs, revealing an ominous presence.
In a shocking twist, Ragini unmasks the killer, revealing it is none other than <actor/v-s-raghavan> as Jambu, who had been pretending to be a cripple and blind. Before dying, Jambu confesses he was neither disabled nor blind and that Ragini was not his biological daughter but merely his nurse. His motive for the murders was greed—he wanted to be the sole heir to Dhayanandam’s wealth. He manipulated Ragini into pretending to be his daughter so that Dhayanandam would accept her into his home.
Following the revelation, Dhayanandam, understanding the truth, distributes his wealth among his siblings and servants as he had wished, and finally succumbs to his illness, leaving a legacy of betrayal, greed, and hidden secrets.
