[1] Mara and Clara were switched at birth, and the details of this event were recorded by Kardo (Dan Fernandez), a hospital staff, in his diary.

The good-natured Del Valle couple (Juan Rodrigo and Beverly Vergel) takes in Mara (Judy Ann Santos) as a servant and decides to spend for her education, not knowing that she is their real daughter.

Gary (Eruel Tongco/William Martinez), who is actually a gang and syndicate leader, approves of the idea that Mara lives with the Del Valles to extort money.

Derick is intern doctor who in love with Mara but his life is complicated as was a victim of force marriage by his girlfriend Mitch (Erica Fife).

After the events of the welcome party, Mara happy as she now lives with her true parents but things are not gonna easy for her as there are still many people who wants to destroy her family: Henry who is his uncle, Inggrid (Glydel Mercado) who helps Henry to destroy the Del Valles by seducing Amante, Roy who seeks revenge after the death of his brother Gary, and Clara who secretly protests her right as a Del Valle's heiress.

After the cancellation of Ula, Ang Batang Gubat, director Emil Cruz Jr. conceptualized a soap opera entitled "Mara Clara" and was presented to ABS-CBN for approval.

On May 19, 1996, cast members Eruel Tongco, Ireneo Sevilla, Joy Clarise Cojuangco and Bienvenido dela Rosa died when their vehicle fell into a ravine in Palayan while driving home from a Nueva Ecija stage presentation.

They eventually removed Gumila's character by the end of Book 1, replaced by Henry as the main antagonist, played by Jeffrey Santos on their second season.

The show's rights was later on purchased by ABS-CBN Entertainment and was moved to an evening slot on July 8, 1996 with its reformatted as a primetime drama series, after TV Patrol to challenge RPN's Tagalog-language dub of Mexican telenovela, Marimar and Villa Quintana of GMA.

The highly-overt antagonism of Gladys Reyes' main antagonist character, Clara, by way of her violent actions done throughout the series against Judy's character, Mara, had provoked a huge reaction on those who viewed the show's protagonist Mara, more favorably, such to the point that Gladys Reyes had earned the title "Bella Flores of the 90's".