Joe Flanigan who was the lead actor in Stargate Atlantis, made a rather short appearance as an FBI agent in this episode. 8 other Actors with Stargate connections appear also in this episode. John Noble (SG1), Trevor Addie (Stuntman) (SG Atl), Michael Adamthwaite (SG1), Sean Carey (SGU) Mark Curtain, (who oddly only has 2 acting credits), this and (SGA), Shauna Johannesen (SGU), Colin Lawrence (SG1), and finally Michael Richards (SG1 & SGU). Also the most senior actor who has worked in Canada extensively, where most of Fringe is filmed, but has never been in any Stargate production whatsoever and almost no Sci-Fi roles is, U.K. born Eugene Lipinsky.
Towards the end of the episode when Olivia is taking Agent Lee to Liberty Island and he scans his hand for admission, a leaf appears on the screen upon which he scanned his hand. The leaf is identical to the leaf shown during breaks used as a secret code for hidden messages.