Shreyan the Bad guy is the main villain in Shreyan the Bad Guy. He is bad and mean to cops.
Shreyan the Police is the twin of Shreyan the Bad Guy and used to be the police chief. Now he sometimes joins the other guys to help fight Shreyan the Bad Guy.
Abhi the Police is the main hero of Shreyan the Bad Guy. He's Shreyan's archenemy and would like nothing better than to get rid of Shreyan the Bad Guy forever. He's the major policeman of STBG. He also works for the coast guard, FBI and CIA.
Since Shreyan the Bad Guy seems to enjoy setting fires, Rishab the Fireman is often called to duty to help. So often, in fact, that he and Abhi the Police are now pretty close pals and are often together on missions to stop Shreyan the Bad Guy.
Rishab the Bad Guy is the twin brother of Rishab the Fireman who helps Shreyan the Bad Guy spread mayhem and distruction.
He is the grandpa of Abhi the Police (and his namesake) and is the chief of the police.
Abhi the Bad Guy is a series of robots with the ability to think and feel, created by Shreyan the Bad Guy to complete the pairs of twins situations (although technically they aren't twins.)