It's a smart move.
Sparks fly, even though the two have almost nothing in common.
After a whirlwind three-week romance, the two become engaged. If she succumbs, he'll call off the engagement. Of course, we've come to realize that the bright, thoughtful Jay is the guy for her, anyway. Like Julia Roberts in that film, Schwimmer has the unenviable task of carrying a film as a disreputable character. He pulls it off by diving into the script's sharp dialogue with humor and cocky charm.