Numbuh 686 was the Decommissioning Squad lieutenant under Numbuh 86 before turning 13 and getting decommissioned.
In Operation: F.O.R.G.E.T., Numbuh 686 hanging out with Numbuh 786 and Numbuh 1086. He is scheduled for decommissioning as he is turning thirteen and is quite happy doing so, claiming that he had a good childhood and regretted nothing. He is very loyal and respectful to Numbuh 86, claiming that he never missed a day of duty, filed all his reports and recaptured over 175 kids for decommissioning, though Numbuh 86 doesn't care much about him at all. He tries to stop her from messing with the Decommissioning Chamber due to it being worked on by the guy who installed the 'Blow It Up!' buttons on shuttles, but she does not believe him and becomes partially decommissioned. He soon regrets becoming decommissioned because he will forget the image of Numbuh 86 slamming a watermelon on top of Numbuh 4's head when her memory returns.
Consolidating Numbuh 786 and 1086