After learning that rent hikes are likely to shutter their beloved Drama Book Shop in early 2019, longtime customers are rallying to support the 100-year-old independent store, which stocks thousands of plays, serves as a go-to gathering place for passionate patrons of the arts, and even plays host to a black box theater in its basement — and has been doing so from its 5,000-square-foot location since 2001 (250 W. 40th St., btw. Seventh & Eighth Aves; visit dramabookshop.com).