Just the Duck (a.k.a. Three's a Couple)

Ellen decides to go Clark's fanciest restaurant all by herself after not finding anyone to go with. There she runs into Catherine, who's on a secret date with Rusty, whom Ellen thought was still hooked up on her since high school. Ellen tags along on their dates, and they decide to break up since it stopped being fun. Their only worry is how Ellen is going to take the break up. Meanwhile, Pam thinks Mr. Munn has a crush on her and Mr. Munn takes advantage of that after Ellen warns him about Pam's feelings.