Mr. Flanigan was Barney's former magic teacher who told him about "The Magician's Code". In The Magician's Code - Part Two, Quinn and Barney plan a romantic getaway to Hawaii. However, in Barney's suitcase is a box which he refuses to open, due to "The Magician's Code". Barney then goes into a long story about Mr. Flanagan, the magic teacher he had who told him about "The Magician's Code", according to which "a magician should never reveal his greatest tricks." Barney also says that Mr. Flanigan was shot by his wife (when she found out that he was cheating on her).