The first season of Ang Probinsyano chronicled around the lives of Ricardo "Cardo" Dalisay and Dominador "Ador" de Leon, identical twins who were separated during childhood.

The story revolves around the journey of twins Dominador "Ador" de Leon and Ricardo "Cardo" Dalisay (both played by Coco Martin), who were separated from each other because of financial reasons, even as they followed the path of being police officers.

He enters the Philippine National Police Academy alongside Joaquin Tuazon (Arjo Atayde).

During his stint in the Police Academy, he meets Carmen (Bela Padilla), sister of his classmate Billy (John Medina).

Cardo is assigned back to CIDG and tackles various cases, some which ties directly to the Tuazon family's criminal acts.