13. Asgard Thinking The Collector Wasn't Up To Something - (Thor: The Dark World)
During the credits of Thor: The Dark World, it cuts to a scene in Asgard with Sif and Volstagg meeting with Benicio del Toro's Collector and a female servant of his. They are there to pick up the Aether - the item that has been the focal point of the entire movie and the item that Malekith was intending to use to plunge the universe in to darkness. They are happy to hand it over to him (despite the fact that he clearly looks like a dodgy character) because, in the Marvel Cinematic Universe, it is one of the Infinity Stones, along with the Tesseract, and having any two of them so close together at any one time could be dangerous. However, the Collector makes it perfectly clear, once Sig and Volstagg have departed, that he intends to gather all six of them when he says "one down, five to go". As a result, by giving him the first one, Asgard has given him a lot of power at his fingertips that he could quite easily use to aid him in collecting the rest - including the Tesseract that they already have. By assuming that he was a nice guy who merely wanted the Aether to look nice in his collection, they've put both themselves and the rest of the universe in potentially grave danger.