Emma works with planning company events. When her sister is getting married, however, she takes a break to help as maid of honor. It soon turns out that the best man is Liam with whom Emma had a failed date a few years ago. Just in time for the wedding the future bride and groom are called away to work, leaving Emma and Liam to arrange all the practical things. It gets off with a bad start, but the more they work together, the more they realize that they're actually not so hopeless.
We've seen the setup before and it works well this time around.