The Big One is a big honey bee made of rubber.
It appeared in the Learn with Sooty episode Have Fun with Numbers when Sooty was counting his honey. Sooty had already magicked three jars of honey and then he went down for his magic wand again stating he was going for “The Big One”. He did magic a Big One but it was not quite what he had in mind. Luckily Sooty did spot the Big One hovering right behind him looking hungrily at his three jars of honey and he managed to magic it away before it away just in time.