One Husband Required summary: Ursula's boss, Ross, invites her to his daughter Katie's birthday party one weekend, saying Katie really likes Ursula and insisted she be there. But this just throws Ursula's heart into chaos. Ursula has had feelings for Ross for a long time now, but she knows he's married. Ursula makes up her mind to keep things strictly professional and agrees to attend the party. But while everyone else is having a great time, Ursula learns just how unhappy Ross's marriage really is.