7
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Tree Torrelli saves Abby and Paige from the group of teenage guys by stating that she is an undercover policewoman, and demanding their names and addresses. The boys scatter. However, Tree's cover is blown, and she cannot continue the investigation on the arson case. The girls apologize.
Tree drives Abby home, where they have dinner and talk about random things. When Abby asks about the investigation, Tree says that she did not learn anything useful. She mentions finding an empty matchbook under a bush that she brought to the office.
Tree leaves, and Abby is guilty about ruining the investigation. She goes in the office to find the matchbook and use her psychic powers on it, trying to find out more about the crime.