Zac Efron [1], his biceps, and his costar Emily Ratajkowski hopped across the pond to London on Tuesday to promote their new movie [2], We Are Your Friends. The two pulled double-duty promotional stops — first at a photocall and later at the premiere — and the hotness levels were almost overwhelming. It's been quite a while since we've seen Zac Efron on the red carpet; he's been in Hawaii for a few months filming Mike and Dave Need Wedding Dates. Don't worry, though, because he managed to squeeze in a sweet weekend with girlfriend Sami Miró [3], quality time with his hot younger brother [4], and plenty of shirtless fun [5]. Keep reading to see Zac's post-Hawaii press trip.