Hit TV shows HEROES and GREY'S ANATOMY are under threat following a proposed walk-out by Hollywood screenwriters. Writers in Los Angeles are threatening to take action over the terms of a new three-year contract, with the current agreement running out on 31 October. The Writers Guild of America wants its members to receive payment when their work is featured on the internet and through mobile phones. Broadcasters claim they have enough episodes of the shows written and in production to last until the end of the year (07). However, schedules could run into trouble in the new year, with broadcasters showing repeats, game and reality shows. A prolonged strike could also affect next year's (08) TV season as pilots for next autumn are being written now. Negotiations are due to take place at the Alliance of Motion Picture + Television Producers offices in Los Angeles on Tuesday (30Oct07)