Starring: Judd Hirsch, David Krumholtz, Rob Morrow, Alimi Ballard
Factual error: During the scene when Megan and the FBI are making the house entry, a scene cuts to two FBI agents, one with a M4 and another with a MP5. The agent with the MP5 has the magazine in his weapon installed backwards. (00:05:10)
Other mistake: The MP5 carried by one of the Federal officers breaching the meth lab has the magazine facing backwards.
Charlie Eppes: Everything is numbers.
Trivia: The episode revolves around a man killing people with the same first names as the thirteen apostles (Mary Magdalene being the 13th), and killing them in a similar fashion in which the apostles died. At one point, Colby and David find a box with a mannequin's head in it. This is a reference to the film Se7en, in which seven people are killed for committing one of the seven deadly sins. The film ends with the main characters finding an actual head in a box.
Question: This question is about the mistake where a SWAT officer has a magazine backwards in his MP5. I know this would be impossible on a real weapon. But, how could it have happened in filming? Rubber cast weapon? Very badly worn prop weapon? Set armourer with a hammer and no clue?