 A second prequel , titled " Vastra Investigates " , was released online on 17 December 2012 . At the end of a case , Vastra and Jenny converse with an officer from Scotland Yard and apologise for Strax 's violent wishes for the culprit 's punishment . Vastra explains Strax 's alien origin as well as her own to the officer , much to his astonishment . Vastra reveals that she was awoken by an extension to the London Underground and initially disliked humans , though that changed when she fell in love with Jenny . On the carriage ride home , Jenny notices it is beginning to snow and Vastra notes that the snow should be impossible because there are no clouds in the sky . 
 A second prequel , titled " Vastra Investigates " , was released online on 17 December 2012 . At the end of a case , Vastra and Jenny converse with an officer from Scotland Yard and apologise for Strax <a href='null_genetive' title='1'><mark>'s</mark></a>violent wishes for the culprit <a href='null_genetive' title='2'><mark>'s</mark></a>punishment . Vastra <a href='uninflect' title='3'><mark>explains</mark></a> Strax <a href='null_genetive' title='4'><mark>'s</mark></a>alien origin as well as her own to the officer , much to his astonishment . Vastra <a href='uninflect' title='5'><mark>reveals</mark></a> that she was awoken by an extension to the London Underground and initially disliked humans , though that changed when she fell in love with Jenny . On the carriage ride home , Jenny <a href='uninflect' title='6'><mark>notices</mark></a> it is beginning to snow and Vastra <a href='uninflect' title='7'><mark>notes</mark></a> that the snow should be impossible because <a href='dey_it' title='8'><mark>there</mark></a> are no clouds in the sky . 
A second prequel , titled " Vastra Investigates " , was released online on 17 December 2012 . At the end of a case , Vastra and Jenny converse with an officer from Scotland Yard and apologise fa Strax  violent wishes ffathe culprit  punishment . Vastra explain Strax  alien origin as well as her own to the officer , much to his astonishment . Vastra reveal that she was awoken by an extension to the London Underground and initially disliked humans , doe that changed when she fell in love with Jenny . On the carriage ride home , Jenny notice it is beginning to snow and Vastra note that da snow should be impossible because it ain't no clouds in the sky .