Jon is singing in the shower about his new girlfriend Heather. While he's doing that, his answering machine picks up a message. Meanwhile, Garfield is feeling tortured from Jon's singing. As soon as Jon gets out of the shower, he checks the time and sees that it's 6:45. He goes to get his little black book of women's phone numbers and dials up Heather's number. But the person who picks up is a man asking Jon why he's calling. Jon tells him that he is Heather's date for the night, but the guy tells him that she's going to dinner with him and hangs up. Jon, heartbroken over another guy at Heather's place, decides to swear off women for good and remain a bachelor.
Meanwhile, at Heather's apartment, Heather gets out of the shower and asks who was on the phone. The guy who answered is actually her brother Mike, who she met up with at the truck stop. Mike is wary about any man who wants to take Heather out on a date while Heather assures him Jon is alright. It's revealed that she was the one who left the message and she wonders why Jon didn't get it.
Jon, now dressed casually, gives Garfield his book and insists that he not give it back to him no matter what. At first, he decides that maybe he could call another woman and asks Garfield to return the book. Garfield tries to, but Jon reminds him not to do it. After another failed attempt, Garfield up and leaves in frustration. Just as Jon is about to order a pizza, he gets the message Heather left him and finds out that Mike was her brother and not another date. Jon asks Garfield for his book back, but Garfield says he hid it somewhere, thinking Job is still testing him. Jon is determined to get his book back at all costs.
Jon makes Garfield a big lasagna (which Garfield calls medium-sized) in hopes that this will persuade Garfield into revealing where the book is. But Garfield still refuses to tell, causing Jon to chase Garfield to get the answer out of him. Just as that goes on, Heather and Mike drive up to the house and find Jon attacking Garfield. Disgusted with Jon's actions on Garfield, Heather breaks up with Jon and Mike tells him to stay away from her. Just as they leave, Jon tries and fails to explain what happened. Garfield reveals that he hid the book in Jon's back pocket. Heartbroken, Jon tells Odie to bury the book in the backyard and apologizes to Garfield for the way he acted. The two of them bond and Heather returns to scold Jon more, but when she sees him and Garfield together, she forgives him and tells him she'll be available tomorrow night. Elated, Jon tells Odie to return the book, but Odie won't show him.
Out in the backyard, Jon is digging it up looking for the exact spot Odie buried it in. Garfield and Odie wish Jon would make up his mind while Jon continues frantically looking for his book.