NXT TakeOver: Unstoppable was a professional wrestling event produced by WWE, under their NXT brand and was broadcast live on the WWE Network, available to subscribers. NXT TakeOver took place on May 20, 2015 at NXT's "home" arena, Full Sail University in Winter Park, Florida and featured six matches as part of the main broadcast and one match prior to the televised portion of the show. The show was the fifth show in the "NXT TakeOver" series of Network exclusive shows. The main event of the show was a rematch from NXT TakeOver: Rival as Kevin Owens defended the NXT Championship against Sami Zayn, the man he had won it from at the previous TakeOver. During the show Samoa Joe made his surprise NXT debut during the main event match. The show included five additional matches including matches for the NXT Women's Championship and the NXT Tag Team Championship.

The NXT TakeOver series of professional wrestling shows started on May 29, 2014 as the WWE developmental league WWE NXT held their second WWE Network exclusive live broadcast billed as NXT TakeOver. In subsequent months the "TakeOver" moniker became the brand used by NXT and WWE for all of their NXT live specials as they held NXT TakeOver: Fatal 4-Way, NXT TakeOver: R Evolution and NXT TakeOver: Rival prior to Unstoppable.

The NXT TakeOver: Unstoppable show featured professional wrestling matches involving different wrestlers from pre-existing scripted feuds and storylines that played out on the NXT television program prior to the show. Wrestlers portrayed faces (those who portray the "good guys") or heels (the "bad guys") as they followed a series of events that built tension and culminated in a match or a series of matches.

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