The narrator, Nick Carraway, describes Gatsby when they first meet as having "one of those rare smiles with a quality of eternal reassurance in it, that you may come across four or five times in life. It faced--or seemed to face--the whole external world for an instant, and then concentrated on you with an irresistible prejudice in your favor. It understood you." Nick also notes on more than one occasion how Gatsby is often called away by the butler for urgent business he must deal with over the phone, a detail that is telling of Gatsby's shady business practices.
Gatsby's background is an unraveling mystery that compels Nick. As far as physical appearance, Nick observes "His tanned skin was drawn attractively tight on his face and his short hair looked as though it were trimmed every day. I could see nothing sinister about him." After Daisy and Gatsby reconnect, Nick notices "But there was a change in Gatsby that was simply confounding. He literally glowed." At the end of the novel, Nick reflects on Gatsby's character and motivation and writes, "I thought of Gatsby's wonder when he first picked out the green light at the end of Daisy's dock. He had come a long way to this blue lawn and his dream must have seemed so close that he could hardly fail to grasp it. He did not know that it was already behind him, somewhere back in that vast obscurity beyond the city . . . Gatsby believed in the green light, the orgastic future that year by year recedes before us."