The episode followed the Fringe team's investigation into random people mysteriously disintegrating into ash, a case which Agent Broyles had become deeply obsessed with in the past.

A Boston man (Joe Towne) is attacked by a shadowy, ghost-like figure; his wife (Michelle Harrison) returns home to find he disintegrates into ash upon being touched.

After learning all of the victims had recently visited a hospital before dying, Agent Broyles (Lance Reddick) explains the case is similar to one he had trouble with in the past, in which his obsessive behavior effectively ended his marriage to his wife Diane.

The suspect, an Eastern European man, had contacted him four years ago sounding distraught and asked him to figure out a special formula, which Broyles was unable to solve.

Despite being ordered to end the investigation and that the suspect is wanted by the Russian government and the CIA, Broyles tells Olivia (Anna Torv) to continue the case.

Fearing capture, Tomas removes his brother from the hospital; Walter speculates that the cosmonaut brought the entity back with him upon returning from space.

The Fringe team is able to trace the call, and Broyles shoots the host (Tomas' brother) in the head to stop the entity from attacking another victim.

It ended up sounding a little like a 1920's [sic] electric chair but had lots of screams and growls as the smoke monster got to vocalize a little bit as he was zapped into submission.

This episode had lots of little electrical things scattered around and I tried to make it sound a little like the Exploratorium in San Francisco, California, with all of its electricity-based exhibits."

Due to the Russian lettering on many of the episode props, director Cassar joked during shooting, "Can we get a translator and find out what this writing means, specifically?

It starts out with the appearance of a smoke monster that kills its victims by enveloping them and leaving behind an exact life-like looking corpse only the body is made of ash which crumbles horribly when touched.

Another VFX supervisor from Zoic Studios, Andrew Orloff, believed the episode's special effects were possibly the most difficult of the season.

[2] Despite liking actor Lance Reddick, Wigler was displeased with his character's increased screentime, believing Broyles works better as an "enigmatic figure".

[2] Wigler did however praise the villain's "murderous method of choice", writing "Those who've read my Fringe reviews know that I'm not big on the mystery-of-the-week element, but I have to give this episode some credit for at least making it look good.

"[2] IGN's Ramsey Isler rated the episode 8.0/10, noting the "great work" done with the CGI and props while at the same time acknowledging the opening was not "particularly exciting".

The monster of the week, an alien stowing away in a Russian cosmonaut's body, isn't all that scary or even malevolent (it's just trying to stay alive by feeding on radiation).

[3] Murray continued that he believed the episode to be "an efficient action/adventure/horror hour, heavy on suspenseful moments and neat effects, light on character development and progress on the master-plot.