Sterling Knight Photos Overview Biography Filmography Photos Sterling Knight during the 32nd Santa Barbara International Film Festival. Sterling Knight as Alex in "17 Again." Zac Efron as Mike O'Donnell and Sterling Knight as Alex in "17 Again." Zac Efron as Mike O'Donnell and Sterling Knight as Alex in "17 Again." Replay Slideshow Previous slide Next slide Thumbnails Play 1 of 4 Advertisement Maximize Share Share on Facebook Share on Twitter Share on Google+ Share on Tumblr Share on Pinterest Share by Email