An elderly Malaysian man goes berserk and kills several Indian officers in a span of five minutes at the Indian Embassy in Kuala Lumpur Malaysia, before collapsing. A tattoo of a love symbol is present at the back of his neck, leading RAW agency to conclude that it is the handiwork of rogue scientist named Love whose identity and whereabouts are unknown to anyone except their agent Akhilan Vinod, who resigned from the agency. 4 years ago, While on an assignment to bust Love, Akhilan's wife Meera George, a leading computer analyst was killed by them. RAW chief Malik tracks down Akhilan and convinces him to join the investigation.

On viewing the video footage of the attack, Akhilan comes to the conclusion that the elderly Malaysian man had taken a mysterious performance-enhancing drug which allowed him to attack the Indian officials and decides to investigate the matter further in Malaysia. Since Akhilan is under suspension, Malik assigns him as a deputy to a junior RAW agent named Aayushi, who is officially assigned to handle the case, and the two of them leave for Kuala Lumpur. In Kuala Lumpur, Akhilan and Aayushi learn that the mysterious drug is inhaled using an asthma inhaler. Further investigations lead them to Peter, a scientist who is on Love's payroll.

Peter becomes informer and tells them about the drug, which is called "Speed". The drug causes a person who inhales it to have extraordinary strength for five minutes before falling unconscious, and if the person inhales the drug again within a few hours, they will suffer a massive heart attack. Peter also reveals that a shipment of 'Speed' inhalers is to be dispatched to Love within the next 15 minutes. Akhilan and Aayushi pursue the lorry carrying the inhalers, but a lorry driver inhales Speed and subdues the duo, which are then taken to Love's hideout. As Akhilan moves to arrest Love, who turns out to be a transgender, he is knocked out by Meera, who is shockingly still alive and has been working for Love as a computer hacker and goes by the name Rosy.

It is then revealed that Meera suffers from retrograde amnesia after being shot in the head 4 years ago and that Love took advantage of her situation to employ her as a computer hacker. However, when Love orders her to kill Akhilan and Aayushi, she points the gun at Love and calls the police, who arrests him. Meera reveals that she had been forced to take 'Speed' by Love to work faster, but the drug caused her old memories, including those with Akhilan, to return, and she soon regained her full memory after continuous use of the drug. Love manages to obtain a 'Speed' inhaler while in custody and inhales it, helping her escape and destroy the entire police station, killing everyone present, including Aayushi. Aayushi had recorded the whole incident by using a Bluetooth camera.

Akhilan finds out that Love had made a satellite call to Chang, the Transport Minister of Malaysia who had allowed Love to send shipments of 'Speed' inhalers to India to perpetrate terror attacks there in return for money. He rushes to the hospital, where Chang is admitted and interrogates him. During the interrogation, Love sneaks into the hospital and, hiding in the air conditioning vent, sprays a neurotoxic gas in Chang's room, causing Akhilan and Chang to get paralysed. She then kills Chang and puts the knife on Akhilan's hand, framing him as Chang's assassin. Akhilan and Meera, who are declared fugitives, but the duo manages to escape from the Malaysian police.

Akhilan and Meera decide to finish off Love using her kill switch activation device, which had been restored and hidden by Aayushi before she was killed. However, as the device can only be opened with Love's fingerprint, they plan on obtaining her fingerprint. They sneak into an illegal airfield owned by Chang, where Love is planning to leave for India with the shipments of Speed inhalers. Akhilan inhales Speed and fights Love, who has also inhaled Speed, and manages to get her fingerprint before collapsing after the drug's effect wears off. On regaining consciousness, he finds out that Love has already left for India.

It is shown that Akhilan used Silica gel to get Love's fingerprints. He then uses the fingerprints to open the kill switch activation device, deactivates Meera's kill switch and kills all of Love's henchmen, including those piloting the plane. The plane crashes into a remote jungle, killing Love, destroying the Speed shipments, and averting a major terrorist attack. One month later, Akhilan and Meera are seen enjoying a holiday cruise sponsored by the Government of Malaysia as a reward for killing Love. After discussing their future plans, Akhilan reveals that he had kept a Speed inhaler and inhales it.