Ever-growing advertising behemoth, WPP, said it has bought the film research firm First Movies for an undisclosed sum.The purchase was made by WPP's communications subsidiary Penn Schoen Berland.First Movies undertakes research for many of the world's major film studios, independent distributors, production companies and industry affiliates, WPP said.It undertakes events like test screenings to gauge audience reactions to new films and clients include Disney, Paramount, Sony Pictures and 20th Century Fox."First Movies' capabilities will complement Penn Schoen Berland's existing media and entertainment practice by giving it a bigger footprint and an increased capability to service its clients' global research needs," WPP said in a statement."This acquisition continues WPP's strategy of investing in important and fast-growing markets and sectors."