The cop had served in Iraq a year previously, and was involved in a secret military experiment called "Project Tin Man".

Peter learns from an old acquaintance the identity of one of the Iraqi doctors; he tells them the project was meant to cure soldiers exposed to a fatal chemical, but it failed to work, instead turning remaining survivors into human bombs.

An AWOL colonel, Raymond Gordon, was opposed to ending the project; Peter and Olivia suspect he is behind the cop's explosion, and caused the deaths by emitting a radio signal.

They return to find the surviving members, and are able to prevent the next subject, Diane Burgess, from exploding after she is contacted by Gordon to take a briefcase at a train station.

Peter and Olivia find Gordon (Stephen McHattie) at the station, and bring him into custody; the man suggests the bombs were intended to eliminate agents working for the Observer.

In a side plot, Olivia and Sam Weiss continue to meet at the bowling alley, where he subjects her to seemingly menial tasks like tying her shoes and keeping score during games.

In one of the best scenes all season, Walter and Astrid are in the lab and, using a watermelon for their experiments, are able to determine the exact frequency that the villain’s generator operates on.

[5] The episode featured the song "The Air That I Breathe" by The Hollies,[1] as well as music from Roy Orbison, Les Paul, and The Marshall Tucker Band.

[7] Peter mentions that his father taught him human reproduction using a jigsaw puzzle of "Ms. July", a reference to a glamour photography shot of an unknown Playboy model used in calendars to differentiate each month of the year.

The story's too simple and the acting too broad, and yet the episode still felt choppy, as though the Fringe creative team had to scramble to fix 'Fracture' in post.

Luckily, that's supposed to come next week with the return of Nimoy's William Bell, which makes tonight's less mythology-oriented outing easier to swallow.