User blog comment:Argorrath/Treyarch posts a message of zombies; possibly hinting to a DLC 4/@comment-50.46.177.41-20130801001343/@comment-4007629-20130801003254

It is possible to feature our original crew, but these letters could just be a backstory... I think you arrived at that conclusion with words such as 'The Doctor,' 'the Motherland,' 'the Emporer,' the like...