Can you handle seeing Daniel Radcliffe play a romantic lead without thinking of Harry Potter? Did you feel like (500) Days of Summer was lacking in real connection? Are you intimately familiar with the "friend-zone"? Do you have a grasp on what it feels like when you have an unreciprocated 'crush'? If you answered "yes" to all of these questions, then there's a solid chance that What If will work a sly bit of magic on you. The film is essentially a rehashing of territory made familiar by When Harry Met Sally, exploring the question so many romantic comedies rely on: can men and women really be just friends? Whatever your actual opinion on this may be (I vote yes), in the world of the Hollywood ending the answer is almost always no. It's a convention of the genre, and the success of the film stems from its ability to play with our expectations, make us question what it is we're asking for, and to make us love (and perhaps, see ourselves in) the characters. In that, What If succeeds where so many have failed. Though flawed, it's smarter than the average, willing to explore uncomfortable complications, and aware of the damage the viewer's wish-fulfillment brings.
Naturally, this is asking the impossible. Wallace is clearly in love with Chantry, and this is a fact that drives Allan and their mutual friends to constantly hound him with options: he has to tell her or he has to get out. Chantry, too, is more subtly torn. She's aware that she loves Wallace as a friend and that he's a driving influence in keeping her from new job. She's aware, too, that Wallace is more present than her boyfriend, who departs for months at a time in his role with the United Nations. The two of them are a bit moody, guilty, and dependent on one another even when they're uncomfortable accepting what that dependence signifies. That the situation is so complicated makes What If weirdly effective. Though the film frequently fights against ideas of realism via the addition of heavily slapstick injuries or little animated bits featuring Chantry's illustrations, it also nails the nuances of this variety of relationship without resorting to villainizing the characters at the fringe.