Written by Malcolm Hulke. The story involved the departure of the Romans from Britain around the start of the fifth century in the midst of clashes against the Celts and the Saxons, culminating with the time travellers fleeing the indigenous savages back to the safety of the TARDIS. "Britain 408 AD" was first submitted on 2 September 1963. Story editor David Whitaker asked Hulke to revise his original storyline as he felt that the plot—with its many opposing factions—was too complicated, and that the serial's conclusion echoed that of "An Unearthly Child" too closely. It was hoped that an amended version of "Britain 408 AD" might occupy the sixth slot of Season One (Serial F), to be directed by Christopher Barry, but on 23 September it was decided that the production block did not need another historical story and Hulke's serial was abandoned. The spot in the schedule was ultimately occupied by "The Aztecs", while Hulke began work on "The Hidden Planet" instead (see above). Following Whitaker's departure, Hulke resubmitted "Britain 408 AD". It was rejected on 2 April 1965, by Whitaker's successor, Dennis Spooner, because the Romans had already featured in his own story "The Romans".