When Mike (voiced by Billy Crystal) was a little eyeball, his class went on a school trip to Monsters, Inc, the company which helped to power the world of monsters through the screams of children they scared when the tykes woke up during the night. Although he was the least popular kid in his class, he had determination and optimism in his favour, so when he saw what was possible at the business he knew his ultimate goal was to be scary and join the ranks of the Scarers, jumping through the doors and out again, pausing briefly to collect a scream. In fact, so keen was Mike that he escaped the group then slipped through one of the doors and caused a panic...
The danger with opening up a fantasy world so carefully crafted as Pixar's Monsters, Inc was that all sorts of questions arise to pressure that construct's credibility, so a prequel such as Monsters University was going to have to nip those issues in the bud by not allowing them to pop into the heads of those watching. That central idea, that this realm could rely so heavily on scaring children, began to look a little flimsy if it was stretched out to another movie, so all credit to director Dan Scanlon and his team that they managed another enclosed world which also operated by its own rules, reminscent of our existence but just alien enough to sustain the fantasy elements.
If taking the story of Mike and Sully (John Goodman) back to the college days threatened to tell us that bit too much, thereby overexplaining things in an origin narrative, at least there were compensations such as Pixar's accustomed generosity of spirit which doesn't get off to a friendly start in this case as Mike is something of an outcast, with only his dream to keep his hopes alive. Here's the drawback, though: we are told throughout that he simply isn't scary enough, so will he turn out to be like some talent show hopeful whose ambition has deluded them and caused them to ignore the fact that they aren't best suited to this line of occupation? What Mike does have in his favour, however, is an excellent work ethic: he may not have a natural gift, but he does have drive.
When Mike meets Sully there is a definite barrier between them; we may know that by the time of the first movie they will be fast friends, but it doesn't start out that way, and again the overexplanation, that gathering of detail we could have worked out for ourselves, was part of what made this prequel that touch inferior. Sully comes from a family of Scarers so takes it for granted that he will pass his exams with flying colours - who needs to study? - but after a scuffle during their first test which infuriates the Dean, Hardscrabble (Helen Mirren at her iciest) they are told they are both off the Scarers' course and assigned to a lesser one. Mike is not having that, obviously, and looks around for another chance.