Chemistry) is a 2006 Indian Malayalam-language family drama film written and directed by Sathyan Anthikkad and starring Mohanlal and Meera Jasmine, with Bharath Gopi, Innocent, Oduvil Unnikrishnan, and Mamukkoya in prominent roles.

Rasathanthram was released in theatres on 7 April 2006 and received positive reviews with critics praising performance of Mohanlal, Gopy and Jasmine.

[3][4] The film performed well at the box office, it grossed ₹21 crore worldwide and completed 100 days theatrical run.

Kanmani dresses up as a boy by the name of Velayuthan Kutty and soon starts working with Manikandan and Premachandran.

Premachandran's brother, Ramachandran, comes to the fray and asks Balan Master to attend his daughter's marriage.

Balan Master takes shelter in an old age home headed by a retired Colonel until a new house can be rented.

But, Premachandran grabs the "thali mala" from Sundara Pandian, ties the knot on Kanmani and subsequently marries her.

Initially Anthikkad thought of giving someone else the scripting duty, but his regular collaborator were busy with other project, so he decided to write the film himself.

[7] Anthikkad describes the storyline as "it is the essence of the chemistry of the duo's life that develops with the rasas (humours) and little thantras (techniques) played by them to earn their living.

The film was shot at various locations in Thodupuzha, Moolamattom, and nearby places in Idukki district.

Rasathanthram grossed ₹22 crore from worldwide box office, becoming the 2nd highest-grossing Malayalam film of the year.