Chase Suno is the main character of the series, and the protagonist. His monster is Lock.

Fifteen-year-old Chase is all confidence and charisma. He is inherently heroic, clever, and loves challenges. When we first meet him, Chase is coping with the disappearance of his father, Jeredy Suno. This is the catalyst that begets his journey with Monsuno. But as Chase learns more about Monsuno, he must rise to the challenge of being a hero. Together with Lock, he must find a way to coexist and create a partnership in hopes of saving the world.

Chase Suno wakes one morning to find his scientist father, Jeredy Suno... gone. A legendary scientist, Jeredy had solved a timeless mystery: What happened to the dinosaurs? He discovered their destruction was by shell-like cocoons barraging the four corners of the earth and what emerged from those...creatures with vast powers at their disposal...Monsuno!

Jeredy Suno was working on the means of controlling the MONSUNO for good, however, his bosses at the ultra-secret government agency, S.T.O.R.M., had a different agenda in mind – they wanted to weaponise the MONSUNO. Jeredy was left with no choice but to take his research and go underground...

But not before he left his only son, Chase, a special gift... a powerful guardian in dangerous times – a riddle waiting to be solved – a force of nature to be directed in positive ways – a Monsuno. And not just any Monsuno – the first Monsuno Jeredy reanimated... and the means to control it!

Chase Suno is now on a mission to master the battle potential of his Monsuno in order to protect himself, to build a team of like-minded Monsuno “Adepts” to take on the forces of evil intent on exploiting Monsuno for personal and political gain... and through all of this... to find his missing father and unlock the mysteries of the Monsuno’s true purpose on earth.