The "Twilight Saga" alum, 21, and the Canadian-Greek actress, 27, are costarring in the action flick, which is filming in New York, and things are said to be heating up on and off the set, according to People.
You may recognize Avgeropoulos from the short-lived
The pair have been looking more than friendly, and on Monday they were photographed holding hands during a SoHo stroll in
"They're happy and having a fun time together," a source told People.
They were seen taking selfies and in mid-June took in a performance of the Blue Man Group, the mag said.
Another source said that as they were leaving the show, Avgeropoulos was struggling with the stairs because she was on crutches, and Lautner allegedly carried her up on piggyback instead.
Lautner has previously been linked to singer and
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