“It’s a wolf in sheep’s skin.”
Alex is 24 years old; he was born in New Jersey, but was raised and lived the majority of his childhood in Philadelphia, Pennsylvania. He arrived in California for the first time when he was moving into his dorm room at USC in Los Angeles, California. Currently, Alex is an alumni from USC with a bachelor’s degree in philosophy.
Alex said that this idiom is similar to a “red herring.” When he used a “red herring” to describe the previous idiom, I still did not understand their meaning. Finally, he decided to explain the idioms as “false positives.” Essentially, the idiom is used when one says a phrase that another finds to be too good to be true. The latter person then asks, “This isn’t a wolf in sheep’s skin, is it?” Meaning, this isn’t a lie, right? Simply, the latter is asking whether or not the former is lying to them about something that would be good if it were true. I had never heard these idioms before Alex told them to me. I have heard similar phrases describing the same idea; for instance, “You’re pulling my leg.”
This idiom, though exemplifying a more malicious intent and meaning, has also been seem in:
Martin, G. (1996). A wolf in sheep’s clothing. Retrieved from http://www.phrases.org.uk/meanings/wolf-in-sheeps-clothing.html