|Japanese name||Hoshiidake Aiga|
He claims to be an expert on a famous thief known as Mask*DeMasque and becomes involved in solving his cases, even managing to retrieve one of the treasures after it was stolen. However, in actuality, he was behind the crimes himself, wanting to further his own fame and wealth.
It started after the first heist, when Atmey discovered Mask*DeMasque's hidden costume and realised his true identity was Ron DeLite. After this he began to blackmail Ron, saying he would keep his identity a secret if he handed over the treasures he stole, sending him also thousands of dollars in return, a small amount of the treasures real value. This continued until Kane Bullard, the CEO of the company that was providing security to treasures threatened by Mask*DeMasque, realised what Atmey was doing and began to blackmail him the same way Atmey was already doing so to Ron.
To deal with the problem he was now faced with, Atmey staged a heist to prepare himself an alibi, then, a few days later, on the day the heist was supposed to be taking place, killed Kane Bullard. At the same time, he had also sent a blackmail letter to Ron, asking him to come to Bullard's office building at the exact time of the heist in order to pin the murder on him. So, Atmey planned to be found guilty of the crime of theft, thus it would be impossible for him to be found guilty of murder. But, before he could be declared guilty of theft, Phoenix was able to deduce what was going on and interrupted the trial. Thus, Atmey was found guilty of Bullard's murder.