|Zac Efron and Lily Collins|
The pair - who briefly dated in 2012 - have sparked rumors they have rekindled their romance after they were spotted holding hands while wandering around the grounds of Disneyland in Los Angeles.
The duo were said to have been in a casual relationship last year, but split after just three months as neither of them were particularly serious about each other and they wanted to focus on their careers.
A source said previously: "It's true that their schedules are crazy right now, which isn't conducive to a relationship being easy."
The 26-year-old actor - who entered rehab earlier this year for alcohol and cocaine abuse - was spotted getting cosy with his 'Hairspray' co-star Brittany Snow at the beginning of the month, but admitted he has been surrounding himself with women to help him forget about his troubles.
However, Zac claimed last year that he struggles going out on dates with people as he finds it "awkward" and would rather do something more spontaneous.
He explained: "Dating is kind of hard. Like dinner or something like that. Like a forced awkward situation is very strange. Especially for me, for some reason. I like to go and do something adventurous. I like to go out and do some sort of crazy activity."