Once again, a special birthday cake is being made for the Delightful Children from Down the Lane. The KND take a trip to the Alamode where tour guide Numbuh 50 Million B.C. tells them about the 1800s KND operatives who were determined to steal the Annoyingly Cute Triplets Who Lived Upon the Hill's Birthday Cake, a delicious cake made by their mother. However, in their attempt to get the recipe, an ice cream trap was set off, freezing over 5000 KND Operatives. It took 10 years to thaw them out, and all were decommissioned since they were technically too old to be KND. All were found except Numbuh 19th Century, the operative sent in to get the recipe and set off the trap, until the current KND recently discovered him. After being thawed out, he's confused by the new modern era, especially with the fact there are now girls in the KND.