Dill Mil Gaye - the re-entry of Dr. Armaan in the show (when Dr. Riddhima and Dr. Siddhant are now married to each other)

Dil Mil Gaye, which started out as a serial depicting the struggles and efforts of people involved in the medical profession, is now turning out to be another Hindi serial in terms of twists and turns. So, a long time back, there was the perfect romantic couple of Dr. Armaan and Dr. Riddhima, but they had to break up, and the characters left the show, with a new set of characters in the show. One of the most prominent one was Dr. Siddhant (played by Karan Wahi); the serial makers must have figured that the ones whom the viewers voted as the most popular ones were Dr. Riddhima and Dr. Armaan, so first they brought in Dr. Riddhima. In true filmy style, Dr. Riddhima did not like Dr. Siddhant, but he liked her. And then came the time when he had to save her from dying of cold, and the way he did this was something that she detested. However, they got married because of family pressure and honor, and then she tried suicide. This caused Dr. Siddhant to get very negative about her, and finally tell her that he detested her. All these were incidents that made the serial become a very dramatic type of Hindi Serial.
And now for something that is even more dramatic, the re-entry of Dr. Armaan into the serial. He does not know about the marriage between Dr. Sid and Dr. Riddhima, and seems to think that Dr. Riddhima is still his love, and waiting for him. Dr. Siddhant knows about the earlier love between Dr. Armaan and Dr. Riddhima, and does not tell him about the marriage, although the other interns at the hospital feel that he should know the truth.

Older Hindi TV serials - Sanjivani on Star Plus - an older medical serial

At any point of time, there can be one or more serials showing on TV that are based on the medical fraternity (with the serials being set on hospitals, on the life of doctors, and on the love life and relationships between them). One of the serials that used to come earlier was known as Sanjivani, coming on Star Plus, in the years 2002-2005. It was a precursor of the later serial, 'Dil Mil Gaye' (that is now coming on Star One). The full name of the serial is Sanjivani - A Medical Boon.
The serial was based on 4 main characters, Juhi, Rahul, Simran and Omi, who are interns in the beginning, having joined the hospital. The medical profession is a demanding profession, with all sorts of people in it, and the serial shows the pressures and demands that the medical profession puts on these 4 characters and the people around them, and how they deal with it and mature (including adding their own context to the people around them). The link of the serial on the Star Utsav site is this link.
The cast of the serial is:
Dr. Juhi Singh/Mehra (played by Gurdeep Kohli) - wife of Dr. Rahul Mehra
Dr. Rahul Mehra (played by Gaurav Chanana / Mihir Mishra) - husband of Dr. Juhi Singh
Dr. Umesh 'Omi' Joshi (played by Sanjeet Bedi) - in love with Chitra
Dr. Simran Chopra/ Mehra (played by Shilpa Kadam / Rupali Ganguly) - first wife of Dr. Rahul Mehra