Hollywood loves a good sequel, but here’s one it could do without: another union strike just months after the town got up and running again from a devastating walkout by writers.

The contract between the Screen Actors Guild and the Alliance of Motion Picture and Television Producers expires Monday, and negotiations have dragged on for weeks with no apparent headway.

SAG leaders have said they are willing to continue talking beyond the contract deadline. Yet their hard-line rhetoric and a squabble with another actors union could put performers on the sidelines, taking electricians, set-builders, caterers, and other Hollywood working stiffs along with them.

A strike in July — or a potential actors lockout if producers decided to play tough — could delay the return of many fall TV shows, which normally would be going back into production then.

With a longer lead time, big-screen movies generally are in good shape through the early part of summer 2009, with studios rushing to finish production on most films before the actors’ contracts expired.

A few films such as “Hannah Montana: The Movie” and Tom Hanks’s “Angels & Demons” could be forced to shut down if a strike occurred. A long walkout could postpone movies scheduled to start shooting late this summer and fall, including Russell Crowe’s “Nottingham.”

Big action films could ride out a short strike by turning to other work while actors were off. Lorenzo di Bonaventura, producer of next summer’s sequel “Transformers: Revenge of the Fallen,” said the filmmakers factored in a hiatus, during which they can get by without actors, working on visual effects instead.

But it would be another blow to an industry that remains in a stall after the writers strike.