Twenty One Grams

Anjali, a biomedical engineer, dies under suspicious circumstances at the city hospital where she worked. Nandan, the Deputy Superintendent, launches a homicide investigation and begins collecting evidence with his assistant Sunny. The case soon centers on whether the death is connected to hospital practices and potential drug trials.

On the next day, Martin, Anjali's brother, is found dead in the same apartment where Anjali was murdered. Nandan and Sunny gather evidence at the scene to establish whether the two killings are linked. The immediate implication is that the killer is someone close to Anjali.

Nandan shifts focus to Jimmy Cherian, a notorious entrepreneur with ties to the city underworld. Murugan, a trusted goon of Jimmy, is arrested but claims Tony has gone missing after the murders. The investigation starts to hinge on Tony's whereabouts.

DNA from the crime scene matches Tony, revealing him as one of the killers of Anjali and Martin. Nandan concludes that at least two attackers were involved, and Tony's involvement becomes a central thread. The confirmation pushes the case toward identifying the second killer.

A call from Tony's fake SIM pings a famous hotel where a party for city entrepreneurs was hosted by John Samuel. Nandan suspects the party might reveal who else was involved in the plot. Video footage from the party becomes a key objective in the investigation.

Nandan asks Nikhil for the party guest list but cannot locate the footage. He later learns that Nikhil is left-handed, a detail that becomes a rare clue in the pursuit of the killer. The clue tightens the focus on suspects and the investigation progresses.

A shadowing car follows Nikhil on his way home and he is found dead in his car the next day. The left-handed clue had pointed toward him, but his death adds a new layer of danger and complexity to the case. The murder deepens the mystery surrounding the hospital and its associates.

Investigators recover a video from Anjali's phone in which she hints at unauthorised drug trials on children at the hospital and says she and journalist Shihab tried to expose them. Shihab died of a cardiac arrest before publication. Anjali tells her brother Martin to publish the evidence, but the documents remain missing.

Martin is killed the next day while pursuing the clues from Anjali's video. The killings escalate as Nandan realizes the case targets both hospital corruption and those trying to expose it. The pressure mounts to identify the remaining killer.

Nandan plans to arrest hospital owner John Samuel as the mastermind behind the murders and the drug trials, but crucial evidence disappears from the Superintendent's office. The disappearance throws the case into doubt and tests Nandan's resolve. The pursuit then shifts toward tracing the last visible links to John.

An old Contessa car with a signature wreath pattern surfaces as a marker of the killer near Anjali's grave. The wreaths are placed with her favorite flowers, implying the killer is someone close to her. Police trace the car to Vinay, Gauri's brother, tying him to the ongoing mystery.

Vinay reveals that Anjali was his girlfriend and that he was prescribed antidepressants; his presence near Nikhil's body raises suspicion although he denies involvement. The drugs and the car connection tie him to the case, testing the loyalties within the investigation. Meanwhile the hospital owner John Samuel remains under protection as the search continues.

John Samuel arrives back in the city and is given police protection, but he is murdered when a man in an old Contessa car slashes his throat. The killer is revealed to be Martin, an apparent ally who has turned against the others. This shocking turn pivots the case toward Martin as the mastermind behind the set of killings.

Contrary to earlier belief, Martin is alive and the killer behind Tony's, Nikhil's, and John's deaths. He eradicates his rivals and manipulates the evidence to maintain control. Nandan chooses to shield his own findings for now, recognizing that Martin's motives are deeply personal as well as criminal.

Sunny reports that the Contessa car used in the killings has been found abandoned in Tamil Nadu; the driver's face is not clear. The police plan to reopen the case to identify the driver, suspecting Tony still has a role. The investigation ends with a unresolved thread and the looming possibility of catching the killer behind the Contessa.