From a boat to a club, Zac Efron and Michelle Rodriguez -- Hollywood's most unexpected couple -- are packing on the PDA.

The seemingly coupled-up pair were first spotted kissing on a yacht, owned by friend and Italian entrepreneur Gianluca Vacchi, while vacationing in Sardinia over the Fourth of July weekend. But if you thought that was a one-time hookup -- you were wrong.

New photos surfaced this week showing the two dancing, laughing and locking lips inside the Porto Cervo club off the coast of Italy on Monday night, two days after their boating adventure.

The 26-year-old “Neighbors” star and the 35-year-old “Fast & Furious” actress were also caught spending the day horseback-riding together before their night out.

But as random as this coupling might be, it turns out they may have hooked up before. According to E! News, the two were introduced by a mutual friend two years ago and have been close ever since.

No word if the relationship between Zac and Michelle will continue now that their vacation has come to an end. Michelle is back to work on "Fast & Furious 7" posting a photo to her Instagram from the set.