Zac & Vanessa Are Reuniting! Find Out Why Hudgens' Boyfriend Austin Butler 'Doesn't Trust' Efron

Is Zac Efron not over his High School Musical sweetheart, Vanessa Hudgens?

The former co-stars and real-life exes are reportedly set to reunite for the fourth film in the franchise, HSM, which has Vanessa's longtime boyfriend worried! According to an OK! magazine source, Austin Butler isn't too thrilled over it.

"Zac still reaches out to Vanessa, so Austin doesn't trust him," the source revealed. Zac and Vanessa dated for years before calling it off in 2010 and eventually moved on to dating other people.

The insider explained that Austin wouldn't allow Zac to be in Vanessa's life anymore, however, he knows that the Baywatch actor "will always be her first love," and "that's intimidating for him."

Do you think Austin should be worried about Zac and Vanessa reuniting? Let us know your thoughts in the comments section!