who plays the characters here?
John Krasinski and Rainn Wilson
A.A.R.M.
 In the episode, Jim Halpert (John Krasinski) convinces Dwight Schrute (Rainn Wilson) that he needs to choose someone to act as an Assistant to the Assistant to the Regional Manager (A.A.R.M.); the two subsequently hold tryouts for the position. 
what episode does jim make a video for pam In the "A.A.R.M." episode which is he collective name for the twenty-second and twenty-third episodes of the ninth season. what is a.a.r.m.? It is the collective name for the twenty-second and twenty-third episodes of the ninth season of the American comedy television series "The Office". what is the aforesaid series all about? It is a mockumentary sitcom that was first made in the United Kingdom and subsequently remade in many other countries. what is the story of the first mentioned television series? UNANSWERABLE what is the story of the first mentioned episode? Jim Halpert convinces Dwight Schrute that he needs to choose someone to act as an Assistant to the Assistant to the Regional Manager (A.A.R.M.); the two subsequently hold tryouts for the position.
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A.A.R.M. [SEP] Introduction
"A.A.R.M." features a dramatic scene in which Jim presents a DVD of the highlights of his relationship with Pam, topped with him finally presenting her with a card he wrote in the second season episode "Christmas Party". The idea to have Jim finally give Pam his card had been considered in the writers' room for some time, but only during "A.A.R.M." did the writers feel it was the right time. In addition, the episode contained several scenes that were purposely staged to be reminiscent of past episodes of the series, with scenes mimicking unique shots in both the third season installment "Gay Witch Hunt" and the sixth season episode "The Delivery".