The Doctor began pacing back and forth, thinking, as she spoke. "We're looking for a transmitter. The Consciousness, which is the ring leader in all this, is controlling every single piece of plastic. So," She stopped pacing and looked at him. "it needs a transmitter to boost the signal." She sighed running a hand through her hair. "It would need to be round and massive, slap bang in the middle of London." She looked so confused it was aborable.