The Battle of Demons Run: Two Days Later (webcast)

 served as a sequel to TV: A Good Man Goes to War and a prequel to The Snowmen. It's notable for explaining Strax's appearance in the latter, as he had died in the former.

Synopsis
In the aftermath of the Battle of Demons Run, a battled-scarred Strax lies dead on the floor — or has he just fainted...?

Plot
Strax is woken up by Vastra and Jenny, and is told that he had not died since they had used alien technology to heal his wounds. Jenny said that he had never truly passed away thanks to the resurrection technology and he had been in a state of unconsciousness for two days while the resurrection device healed him. He's angry about not having died. Vastra and Jenny then announce that the station is being evacuated, and they offer to take Strax with them back to London. Strax is hesitant and at first rudely refuses but then changes his mind and agrees to accompany them.

Cast

 * Strax - Dan Starkey
 * Vastra - Neve McIntosh
 * Jenny Flint - Catrin Stewart

Crew

 * Writer - Steven Moffat

Story notes

 * This story was only made available in the United States of America.

Continuity

 * Strax was struck down by a Headless monk. (TV: A Good Man Goes to War)
 * Strax teamed up with Vastra and Jenny. (TV: The Snowmen)
 * Strax later uses the alien technology used to heal him to attempt to save Clara Oswald, but her injuries were more severe than his.(TV: The Snowmen)