Ted and Marshall hijack Barney for what is his surprise bachelor party. The timing of their hijack leaves Robin high and dry to spend dinner alone with Loretta, to which Robin is not looking forward. Barney, who coins his party as his "bro mitzvah", is quietly excited for what most men would define as one of the defining evenings of their life. However, he is skeptical that Ted and Marshall can pull off his dream bachelor party, as most men's bachelor party is like a standard evening out for Barney. But Ted and Marshall are confident that they can do his party justice, especially as they paid attention to Barney's previous description of his dream bachelor party. But will Ted and Marshall's interpretation of Barney's description match Barney's own?