
Trivia: Stan Lee makes his usual cameo, this time as a patient at the asylum where Selvig is being held.

Continuity mistake: In the scene where Thor tells Jane to hold on, she's on Thor's right side and Mjölnir (the hammer) is in his left hand. As they are traveling through the Bifröst to Asgard, the position of each has changed. (00:28:20)
Answer: Loki has been shown to exhibit numerous powers in the movies that can explain how he knew about this conversation. In all the movies, he has been shown to appear in hologram-like forms in different locations. For example, in The Avengers, he uses this power to meet up with The Other who is in the middle of space, whilst he is on Earth. In the end credits scene for Thor, he was able to watch over Selvig and Nick Fury's conversation despite not being there. In Thor: Ragnarok, he was able to see into Valkyrie's past through touching her head (though this power was not established until Thor: Ragnarok). Any of these powers could have been used to find out about this conversation between Thor and Odin.
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