Shelley Catherine "Shell" Hennig (born January 2, 1987) is an American actress, model, and beauty pageant titleholder. She won the 2004 Miss Teen USA competition. On television, Hennig is known as Stephanie Johnson on the soap opera Days of Our Lives (2007–2011, 2017), Diana Meade on The Secret Circle (2011–2012), Malia Tate on Teen Wolf (2014–2017), and Ava Winters in the Netflix action comedy Obliterated (2023).

Her film appearances include Ouija (2014), Unfriended (2014), and When We First Met (2018).