As Brittany and Santana plan their wedding, Artie is recruited to be the wedding planner. While Santana struggles with the fact that her disapproving grandmother - with whom she hasn't spoken since coming out as a lesbian - refuses to attend, Brittany takes matters into her own hands. Fresh off their unexpected win at Sue's Show Choir Invitational, Rachel and Kurt give the gleeks their weekly assignment: the music of Burt Bacharach, and recruit reigning diva Mercedes to act as a mentor for the new singers. While Mercedes is supportive of Rachel's new career path, she is committed to convincing her to not abandon her dreams of something bigger and better... namely Broadway. To that end, she tells Rachel she's arranged an audition for her for a new, upcoming Broadway musical, and tries to inspire a resistant and gun-shy Rachel to take another shot at her dreams of stardom. Meanwhile, despite agreeing to stay just friends, Rachel and Sam try to negotiate bigger feelings they may or may not have for each other, but it takes the advice of an interested third party to move things along; and Brittany learns a shocking family secret, including the origins of her remarkable mathematical prowess.
