hi,I'm from Osaka.めっちゃ is Osaka word. めっちゃ話is wired.めっちゃis very　or so(とても、すごく). 例：めっちゃうれしい＝I'm so happy. 形容詞や動詞の前につける言葉です。名詞の前にはあまりつけません。

Jimmy's answer is wrong. めっちゃ話 is weird(not 'wired') as Mizuki　Ogasahara-san wrote. I think that it is a part of a sentence like "めっちゃ話が長い／おもしろい", "めっちゃ話（が）飛んでる", "めっちゃ話（を）振られた". You(Татьянаさん) should quote longer.

It means like "a true story"