The Big Bang Theory season six finale, "The Bon Voyage Reaction," features a major turning point where Raj Koothrappali overcomes his selective mutism following a breakup with Lucy. The 2013 episode also centers on Leonard accepting a research position in the North Sea, prompting jealousy from Sheldon. For more detailed information and trivia, visit The Big Bang Theory Wiki . The Bon Voyage Reaction | The Big Bang Theory Wiki | Fandom