Modhalum Kaadhalum

• Ashwathy Ash as Dr.Vedha
  • A doctor, Tamils Family, Kaveri and Subramani 's daughter, Vikram's second wife, Tanvika's stepmother.
• Sameer Ahamathu as Vikram
  • a Telugu speaking person, Gajalakshmi and Ravi's son, arrogant businessman, Tanvika's father, Mirnalini's ex-husband.
• Baby Aazhiya as Tanvika
  • Mirnalini and Vikram's daughter, Vedha's step-daughter.
• Swathi as Mirunalini
  • Vikram's 1st wife, Tanvika's biological mother. (Main Antagonist)
• Fawaz zayani/ Varun udhay as Aadhi
  • Vikram's rival, Mirunalini's boy friend.(Main Antagonist)

• Girish as Subramani
  • Vidhya and Vedha's father, Kaveri's husband.
• Uma Padmanabhan as Kaveri
  • Vidhya and Vedha's mother, Subramani's wife.
• Hensha Deepan as Vidhya
  • Kaveri and Suberamni's daughter and Vedha's sister.
• Sathya Sudha as Vidhya's husband.

• Nalini as Gajalakshmi
  • A Telugu Women, Ravi's wife, Vikram and Nandhini's mother, Tanvika's grandmother.
• Kavithalayaa Krishnan as Ravi
  • Gajalakshmi's husband, Vikram and Nandhini’s father, Tanvika’s grandfather.
• Ramya Ramakrishna/Sridevi Ashok as Nandhini

• Santhosh as Vasanth
  • Vikram’s friend, as well as his assistant at his company.
• VJ Kalyani as Shruthi
  • Nandhini’s sister-in-law.
• Sudharsanam as Siddarth
  • Vedha’s ex love interest / Vidhya's brother in law
• Geetha Narayanan as Vidhya ’s mother in law.
• Shankaresh Kumar as Raganathan.
  • Vedha’s ex-fiance
• Sudhakar as Ram
• Vetrivel as Adhi

Initially, the title of the serial was named Vikram Vedha.[5] Later renamed as Mothalum Kaadhalum, because of the 2017's Vikram Vedha film produced company give the copyright issue.[6][7]

Tamil actor Sameer Ahamathu was cast in the male lead role as Vikram, who is an arrogant businessman and single father.[8] Marking her return after Sillunu Oru Kaadhal, Malayalam television actress Ashwathy Ash was cast as the female lead Vedha, a Tamil family background, A hard-working woman, she struggles with her marriage.[9]

Fawaz Zayani was cast as main antagonist Aadhiya,[10][11] but was replaced by Varun Udhay on 22 September 2023.[12] Initially, Janani was chosen to play as Mrinalini but she declined. Later, Swathi cast to play as Mirnalini Vikram's ex-wife.[13][14] Actress Nalini was cast to play Vikram and Nandhini's mother as Gajalakshmi,[15] Kavithalayaa Krishnan was cast as Gajalakshmi's husband. Ramya Ramakrishna played Nandhini, but in August 2023, she quit and was replaced by Sridevi Ashok.

Uma Padmanabhan cast to play Vidhya and Vedha's mother mother. Baby Aazhiya, recognized for her roles as Jr. Aishwarya in Idhayathai Thirudathe 2, was selected to the lead character as Tanvika, who is the daughter of Mrinalini and Vikram. In July 2023, actor Sundhakar was cast as Ram.[16] In October 2023, actor Vetrivel was cast as Adhi.[17]

The first promo of the series named Vikram Vedha was released on 24 March 2023 featuring Sameer Ahamathu and Ashwathy Ash an ego clash between Vikram and Vedha.[18] However, a some legal problem, later renamed as Modhalum Kadhalum: Vikram Vedhavin Kathal Kadhai, the new promo was released on 6 April 2023.

The show started airing on Star Vijay on 24 April 2023 on Monday to Friday at 18:30 (IST), replacing Raja Rani 2 time slot.[19]