Surprise summer hit “The Smurfs” finished second with $21 million domestically over three days, followed by sci-fi Western “Cowboys & Aliens” with $15.7 million.

New body-switching comedy “The Change-Up” finished fourth with $13.5 million, at the low end of forecasts.

“Rise of the Planet of the Apes” was released by 20th Century Fox, a unit of News Corp. “The Change-Up” and “Cowboys & Aliens” were distributed by Universal Studios, a division of Comcast Corp. . Columbia Pictures, a unit of Sony Corp, released “The Smurfs.” (Reporting by Lisa Richwine; Editing by Doina Chiacu)