PERHAPS it was their primal fear of Edward Norton. In any event, his phone calls persuaded corporate sponsors to underwrite $20 tickets – for every seat, for every play – for the Signature Theatre Company’s next four seasons.

“Edward made the first phone call to our office,” TimeWarner’s Dan Osheyack revealed yesterday – and, turning to look at the lanky star, he added, “No one believed it was you!”

The off-Broadway theater company was a launching pad for the “Primal Fear” star, who performed Edward Albee’s “Fragments” there in 1994 before becoming a trustee and board member. Albee, Norton, writer/performer Bill Irwin and others returned to the theater yesterday to announce its new ticketing policy and the company’s plans for the next four seasons.

Highlights include works both new and old by Albee, Charles Mee, Suzan-Lori Parks and Tony Kushner – and, of course, those $20 tickets. For more information, visit signaturetheatre.org or call (212) 244-PLAY.