The Bob Zemeckis guessing-game continues.The helmer, who likes to take as much as 18 months between pics, is sniffing around an untitled project at Warner Bros. The project, scripted by Barra Grant, was called “Intervention” when it was set up at Turner Pictures, before the small film company was folded into Warner Bros. last year. Zemeckis publicist Paul Block said that the “Forrest Gump” helmer has not made any decisions about what his next pic may be, just that he’s considering the Barra script as a possibility. But that could throw a wrench into his relations with DreamWorks, where he, Steve Starkey and Jack Rapke have set up a lucrative first-look deal. “I don’t think DreamWorks would want to see Zemeckis do his next movie for anyone but them,” one industry source said. Block countered: “He’s developing several projects. He doesn’t know what he wants to do next. He read a first draft of this and likes it enough to take it to the next step and develop it.” The project is a small-scale drama about an engaging alcoholic who is confronted by his estranged wife and three of his best friends at a surprise party.