The One Doctor is a Big Finish Productions audio drama based on the long-running British science fiction television series Doctor Who. Plot The Sixth Doctor and Mel come up against an impostor Doctor and his companion Sally-Anne. During the serial, the Doctor and his companions undertake a quest to find the three greatest treasures of the Generios system. The story was essentially Big Finish's Christmas panto, and features an extra Christmas scene as a hidden track at the end of the story. The episodes are heavily laden with comedy such as the impostor Doctor's name, Banto Zame, seeming to be an intentional rhyme with Panto Dame. The Shelves of Infinity Banto Zame and Mel Bush arrive on Generios Eight to try to locate one of the treasures, The Shelves of Infinity (Unit ZX419). The Shelves of Infinity were designed and created by the Assembler race on Generios Eight, considered the pinnacle of their race. The pieces that make up the shelves are constantly phasing in and out of this dimension, so they can never be completely assembled. The Shelves of Infinity were stored in Warehouse ZX under the code ZX419. Banto and Mel encounter the Assemblers and manage to convince them to let them take unit ZX419, but only if they could assemble it. Banto scoffs, saying it will be easy. Once the two start building the shelves, they notice parts are going missing. The instructions make sense, but they never get any closer to actually building it. Eventually, they come up with a way to fool the Assemblers: since the building process can never be finished, the Assemblers do not know what the finished product would look like. The Assemblers are fooled long enough for the Doctor to arrive in the TARDIS, and Banto and Mel escape with the Shelves of Infinity. Mentos Another of the treasures, Mentos (also known as the Mentos Device), is an advanced computer and information retrieval system. It is one of the three treasures of the Generios system in the far future, described by the Doctor as the "vulgar end of time". Mentos appears in our universe as a small metal box that projects the holographic image of an old man which acts as its real world interface. The box is actually a portal to a shadow universe which is populated by countless information collectors—research devices that travel through time and space, constantly seeking