Rey and Master Skywalker
Excluding the ending, Luke Skywalker was completely absent from Star Wars: The Force Awakens. After his nephew and star pupil, Ben Solo, a.k.a. Kylo Ren, turned on him, Luke retreated to parts unknown. Now that Rey has found out where Luke is, it is time for her to be trained in the ways of The Force.
Both Daisy Ridley and Mark Hamill have described the relationship between the two as tense. This is understandable considering both of the characters’ pasts. Rey grew up relying on herself and answering to no one. Luke’s best student (who was also his nephew) betrayed him so there is no doubt that his confidence is shook by his experience. So now these two have to come together to stop Luke’s nephew and the organization led by a mysterious figure who seems to know a lot about the Jedi.
The film’s title, The Last Jedi, in fact refers to Luke Skywalker himself. In the trailer, Luke’s voice over mentions that “it is time for the Jedi to end.” As with most trailers, this was probably taken out of context. But it still worth noting as to what the future holds for the two. If the voice over was literal, why is Luke training Rey if he wants the Jedi to end? Could Rey be the beginning of a new Jedi order that Luke is trying to establish?