is it a film?
No, it's an American television series
Agents of S.H.I.E.L.D. (season 4)
The fourth season of the American television series "Agents of S.H.I.E.L.D.", based on the Marvel Comics organization S.H.I.E.L.D., follows Phil Coulson and other S.H.I.E.L.D. 
when does the new season of marvel's shield start May 2017
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Agents of S.H.I.E.L.D. (season 4) [SEP] Introduction
The fourth season of the American television series "Agents of S.H.I.E.L.D.", based on the Marvel Comics organization S.H.I.E.L.D., follows Phil Coulson and other S.H.I.E.L.D. agents and allies after the signing of the Sokovia Accords. It is set in the Marvel Cinematic Universe (MCU) and acknowledges the continuity of the franchise's films. The season was produced by ABC Studios, Marvel Television, and Mutant Enemy Productions, with Jed Whedon, Maurissa Tancharoen, and Jeffrey Bell serving as showrunners. Clark Gregg reprises his role as Coulson from the film series, starring alongside the returning series regulars Ming-Na Wen, Chloe Bennet, Iain De Caestecker, Elizabeth Henstridge, and Henry Simmons.