Scientists make a startling discovery in the Antarctic, a Yeti-like snow creature frozen in a block of ice! Meanwhile, Jerry informs Sam, Clover and Alex that there have been reports of a strange being terrorizing a posh ski resort. When they arrive to investigate the luxurious place, they find that they aren't the only ones on the case until they meet Martin Mystery, a teenage paranormal investigator working for the Center – an organization much like WOOHP!

In the B-story, the girls all develop a different relationship with Martin;

Clover was initially hit on by Martin and tried to flirt with him, but got rejected.

Sam was compared to Martin's step-sister, Diana Lombard, much to her annoyance.

Alex started to bond with Martin over their love for video games.

Diana learns that CIHL stands for "Creature Intelligence Hybrid Laboratory" and starts to fight against it. However, she becomes overpowered by monsters who were once Octavia Paine's agents (Octavia Paine just used her). She was turned into a half-lizard, half-girl hybrid by Octavia Paine, a former Center agent who also did not get a good evaluation. Then Octavia creates the "Ultimate Monster" from the stolen monsters and sends it to get revenge on M.O.M. Martin and Diana work as a team to defeat it. In the end, Diana got an upgraded evaluation while Martin got a downgraded evaluation and the Center welcomed her back, making things go back to normal.

Diana resigns from The Center for not having a good evaluation and joins a rival paranormal organization called the CIHL and starts stealing Martin's monsters.

Diana decides to resign from The Center and joins CIHL and shocks Martin, Java, Billy, M.O.M. and the members of The Center. After being armed with CIHL gears and weapons, she goes after Martin's assigned monster. Let's just say this is a transformation.