"Transmission Failure" Here's my interpretation of how Gordon miraculously ended up inside the train at the beginning of Episode 2, despite him clearly standing outside on the platform at the end of Episode 1. Both Gordon and Alyx likely run inside the passenger car before the car that gets propelled by the citadel explosion radius smashes into the platform. As for Alyx, given how the G-man starts to show more of an interest in Alyx rather than Gordon, he probably does something to save her, since she appears completely unharmed at the beginning of Episode 2.
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