This is apparently a real story: Costume for Red Sox Mascot Wally the Green Monster Stolen From Fenway
“Police said they believe the thief was wearing the costume. At about 2:22 p.m., a security officer at Fenway reported the theft. The thief was last seen at Boylston and Dartmouth streets.
Wally was seen around 1:30 p.m. walking in Copley Square during the summer arts festival. It’s unclear how many Wally costumes there are.”