Stargate SG-1, Episode 3.14, Foothold.   When Teal'C and Carter realize that a "foothold" situation exists at the SGC, they devise a plan to gain outside help.  Carter escapes the base and arranges a D.C. meeting with Maybourne. Unbeknownst to her however, an alien impersonating General Hammond contacts Maybourne as well and convinces him that Carter is delusional due to exposure to a nerve gas. More aliens, disguised as O'Neill and Jackson, show up at Carter and Maybourne's meeting where it is mutually agreed that all four will fly back to Colorado.  Once aboard the plane, the aliens' plan begins to unravel.

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