Gwyneth Paltrow and Jerry and Jessica Seinfeld are hosting a starry showing of Jake Gyllenhaal’s new movie, “End of Watch,” Sunday in East Hampton. Ingrid Sischy and Sandra Brant will also host the Open Road Films event at the Goose Creek screening room. Gyllenhaal will attend even while he’s deep in rehearsals for his US stage debut in Nick Payne’s “If There Is I Haven’t Found It Yet,” which starts previews next week. The show opens on Sept. 20, a night before Gyllenhaal’s film.