| Actor | Character | Description | Season 1 | Season 2 |
|---|
| Deepa Balu | Dr.Rina Vijay | A compassionate and resilient surgical resident who is the biological daughter of renowned surgeons Radhi and Vijay, navigating her career while trying to reconnect with her parents and complexities of their strained relationship. She often finds herself in trouble for prioritizing her patients' well-being over strict rules. | Main |
| Kanishka Vijaykumar Y | Guest |
| Anumol | Dr.Radhi Thiyagarajan | Rina’s biological mother, A strict and workaholic chief surgeon known for her professional brilliance, who struggles to balance her career with a complicated personal life and a strained relationship with her past. | Main |
| Sachana Namidass Y | | Guest |
| Charukesh M | Arjun | The supportive and loving son of the hospital's founder, who becomes the CEO and Rina's love interest, navigating professional challenges while being a steadfast presence in her life. | Main |
| Karthik Kumar | Dr.Vijay | Rina's biological father and Radhi's former lover, whose unexpected return adds a layer of complexity and drama to the lives of the two main characters. Initially comes to RK Hospital from Mumbai as a medical investigator, now works in RK Hospital as a senior doctor. | Mentioned | Main |
| Roshan A Y | | Guest |
| Mohan Raman | Thiyagarajan / "Thayagu" | Radhi's father | Guest | Main |
| Sabaresh | Dr.Ramakrishna "Rocky" | A lighthearted and humorous medical intern who provides a comedic touch and much-needed relief to the intense atmosphere of the hospital and a close friend to Reena | Main |
| Yogalakshmi | Dr.Tejasri "Teju" | A relatable medical intern and a close friend to Naveen and Rina, who struggles with the immense pressure of her residency while trying to maintain a normal personal life. | Main |
| RG Ram | Dr.Naveen | MNM's estranged younger son; A fellow medical intern. He is often part of the group of interns, navigating the challenges of their residency and personal lives and close friend to Teju and Rina | Main |
| Padine Kumar | Dr.Anitha | Another senior medical intern. She is a versatile and dedicated professional who often works closely with Dr. Ravi. Her character goes through a "rollercoaster" of emotional shifts throughout the series. | Main |
| Guru Lakshman | Dr.Ravi | A senior intern at the hospital. He is often seen alongside fellow senior intern Dr. Anitha, and their close relationship is a topic of speculation among the other interns. He is a dedicated professional but can be emotionally vulnerable, as shown when he freezes during a critical surgery. | Main | Mentioned |
| Sarvhaa | Dr.Guna | Another medical intern who is a close friend of Rina and Rocky. He is depicted as a supportive and reliable member of the intern group. | Main |
| Amit Bhargav | Madhan | MNM (who is the rival of RK)'s eldest son; A recurring character who is always present and often adds to the drama. His character is noted for not giving off "villain vibes" despite being one of the more straight-up antagonists in the show. | Main | Recurring |
| T. M. Karthik | Dr.Preetham | A manipulative and ill-willed doctor who tries to create discord among the hospital staff to usurp the CEO's position. | | Main |
| Jayarao | Dr. RK | The chairman and founder of RK Multispeciality Hospital and Arjun's father. He is a key figure in the hospital's power dynamics and is concerned about his son's reckless behavior, hoping a good marriage will bring him stability. His declining health becomes a central point of drama in the series. | Main | Mentioned |
| Chandrasekar Koneru | Dev | Radhi's husband | Main |
| Sharmila Thapa | Aruna | A senior nurse in RK Hospital | Main |
| Ashwathy Agnihothri | Manasa | MNM's daughter; a psychologist; She returns and informs Madhan (one of her brother) that she wants the hospital back, suggesting she has a past connection to the hospital and an agenda of her own. | Mentioned | Main |
| Riya Manoj | Divya "Divi" | Radhi and Dev's daughter | Main |
| Diyansh K | Sid | Radhi and Dev's son | Main |
| Akshathaa Ajit | Dr.Nilofer | A new medical intern who joins RK Multispeciality Hospital in the second season. She is a dedicated young doctor whose personal life, including an engagement, becomes a part of the series' storyline. | | Main |
| Shivaraman M | Dr.Kiran | A new medical intern who joins the hospital in the second season. He is depicted as being interested in his colleague, Nilofer. | | Main |
| Abdool Lee | Dr.Kamalakannan | A doctor at the hospital who gets confused by Amaya's twin sister, Abinaya, leading to a key moment where Amaya's lies are exposed. | | Main |
| Roshni | Ramya | One of the nurses in RK Hospital and a mysterious character with a hidden identity, whose lies about having a twin sister are eventually exposed, causing major plot twists. | | Main |
| Abinaya | an Unemployed; Amaya's twin | | Recurring |
| Kavithalayaa Krishnan | Ganesh | Thayagu's friend and Radhi's neighbor who adopted Rina as his daughter | Main |
| Devishree | Sharadha | Ganesh's wife | Main |
| Sindhu Shyam | Jennifer | A Classical dancer; Suryakant's ex-wife; Guna's mother | Recurring |
| Giri Dwarakish | Dr.Ramanathan "Cinema Doctor" | An amusing character known for his love of cinema. He is a senior figure at the hospital who provides a lighter, more entertaining dynamic to the series. | Main | Recurring |
| Syamantha Kiran | Suchitra Madhan "Suchi" | Madhan's wife | Recurring |
| Varshini Suresh | Sonia | Rina's best friend since childhood who settled in Kolkata by marriage | Recurring |
| Sherin Farhana Y | Guest |
| Revathi Elango | Bharathi | Ravi's cousin turned wife | Main | |
| Aruljothi Arockiaraj | Charu | Ramanathan's daughter; Rocky's love interest | Recurring |
| Samridha Sam | Agalya Madhan | Madhan and Suchitra's daughter | Recurring |
| Riyaz Khan | Suryakant | An actor; Jennifer's ex- husband and Guna's father | Guest |
| Indumathy Manikandan | Pallavi | RK's wife and Arjun's mother | Guest | Mentioned |
| Dasarathy | MNM | RK's business-rival; Father of Madhan, Manasa and Naveen | Guest | Mentioned |
| Saravanan Rajavel | Kishore | RK hospital's compounder | Recurring | |
| Gaayathri Krishnan | Rani | Ravi's mother | Recurring | |
| Aghalya | | Teju's mother | Recurring |
| Theni Murugan | | Teju's father | Recurring |
| Nila | | Amaya and Abinaya's mother | | Recurring |
| Jairam | | Amaya and Abinaya's father | | Recurring |
| Vetri Kiran | | Nilofer's father | | Recurring |
| Yogi | Murugan | Rina's hostel warden | Guest | |
| Bose Venkat | | | Guest | |
