When Sharapova was inducted into the Tennis Hall of Fame on Saturday night, her former on-court antagonist provided the introduction. For many tennis watchers, Williams’s top-secret cameo was shocking but the moment capped a 180-degree turn in their once pointy rivalry.

Williams' surprise appearance to induct Sharapova was "months in the making" and required the code name of another female icon.

Serena Williams and Maria Sharapova are friends now? The shocking Hall of Fame induction has fans reeling over forgiveness and the intense media narratives that once defined their rivalry. Get the full story.