Originally Posted by Jaxon
I doubt Odin is imprisoned somewhere, more suspect that Odin was off on another world for some reason and Loki just used that time to try and influence Thor to go and live on Earth, which is what I got out of what Thor said.
The really tricky thing is how he gets passed Heimdel all the time. But with his presumed death I suppose Heimy isn't looking for him.
Heimdall can't see through Loki's illusions. That's how he could get the frost giants into Asgard in the first movie. When Loki "died" Heimdall wasn't in service (he might still not be). We didn't see what happened to Heimdall but they wouldn't have sent a solider to Svartalfheim if he was around to gaze.