Theory:Doctor Who television discontinuity and plot holes/Orphan 55


 * Why didn't the TARDIS translate that Russian sign for Graham and Yaz?
 * Maybe because they were too far away from it.
 * Agreed. The TARDIS didn't go with them, possibly leading the translation circuitry to disconnect. Or maybe the transportation cube was responsible.


 * Why does Ryan address Graham by name, after having decided to call him "Granddad" by the end of Series 11?


 * 1). How can the world be uninhabitable in the lead-up to its destruction when The Sontaran Experiment showed that it was still inhabitable?
 * 2). How can the future be "only a possibility" that can be avoided when it has been shown on multiple occasions that the exact opposite is the case?
 * I agree. There are fixed points in time in the future that conflict with this episode.  Perhaps they are somehow not in their own universe any more (Tennant's Dr went to the Doomsday universe in Journey's End).  And perhaps the transport they used that took them to Orphan 55 came from a parallel universe.  Maybe Tennant brought it back from the Doomsday universe. If so, and since the Dr was surprised that Orphan 55 was earth, then she was probably shocked that this happened to Rose's new earth.  Also, that would mean that she knew it wasn't the earth from her universe and that this isn't one possible future.  Perhaps it's what she thought the companions needed to hear.  Which means she lied about "one possible future", but that would be rule #1.  The Dr lies.