Tamil cinema has offered noteworthy thrillers so far and they actually remain memorable for their slick execution and their deeply impactful moments. Ramkumar's Ratsasan stands among the best ones ever made in Tamil cinema. This 3-hour psycho-thriller starts with a very promising intro scene which reveals to us that the film will mainly depend on the mysterious murders that are happening in the city. Ramkumar introduces us right from the beginning to what we are going to experience in the film. The specialty of Ratsasan unlike the previous thrillers is that the director is sticking us with this suspense throughout the whole film. During this, we get to witness an aspirant filmmaker turning into a police officer, his family and his bonding with them, a teacher and a deaf and dumb child, another teacher who misuses his students, and an arrogant police officer who spoils everything. All these subplots are connected to the main plot of the film which revolves around the serial killings of young girls. Even with all these subplots, the film doesn't lose its pace because the director sets us that our only motivation as an audience is to watch Vishnu Vishal's journey to track down the notorious serial killer. Ratsasan is a very different commercial film because it has no dance numbers, no love tracks, no comedy tracks, and no unnecessary things that will ruin the film's pace. The film starts on a lighter tone when establishing the characters but after the interval, the film becomes as serious as it can be. The dark and gritty second half is well packed with twists and turns which serve as the film's main engagement factors. Speaking about the cast, they have all contributed to making this film as impactful as it should be for its strong content. Vishnu Vishal has one of his suitable characters and his performance as Arunkumar makes us want more from him. On the other side, we have Amala Paul, Munishkanth, Abhirami, Suzane George, and Kaali Venkat in the supporting roles scoring well in their given space. The real show-stealer of Ratsasan is Saravanan who plays the main antagonist roles: Christopher and Mary with so much hard work and dedication. We can clearly see on the screen that he has given his best through this film. Even with his minimal dialogues, Saravanan proves his capabilities as an actor taking the role seriously with excellent body language and appearance. Hats off Saravanan and Yasar (young Christopher)! Ratsasan works brilliantly for its adrenaline-rushing background score done by the promising Ghibran. There's no doubt that Ghibran is the heart and soul of Ratsasan. His brilliant background score brings us to the edge of our seats while giving us thrilling moments in the film. A round of applause for Ghibran! Technically, Ratsasan is a well-made thriller. The editing and the cinematography are simply outstanding. Ramkumar has delivered one of the finest films of Tamil cinema. The screenplay is well-written which is why Ratsasan is effective. The flashback portion is so hard-hitting and has a very subtle message that people should recognize. Ramkumar's work should be appreciated for the fact that he has brought a totally different film from his previous comedy Mundasupatti. It's so interesting to see a director who's capable of doing a full-fledged comedy film and an intense psychological thriller in a short span of time. Salute Ramkumar! Except for a few logical mistakes, Ratsasan is a well-researched film and Ramkumar has made sure that the film has a lasting impact through its edge-of-the-seat narrative. Overall, Ratsasan is A MUST-WATCH PSYCHO-THRILLER!