I will never forget first seeing Rob Reiner’s “This is Spinal Tap” in 1984 at the Varsity Theatre in Chapel Hill. One of the highlights of the hilarious experience was a shot of a venue identified in the film as “Vandermint Auditorium, Chapel Hill, North Carolina” – which made the audience go crazy (too bad no such place exists). Local movie fans may react the same way on Saturday night, when the classic comedy screens at the N.C. Museum of Art’s open-air theater as part of its 30th anniversary celebration. For the uninitiated, the incredibly funny film, a savage satire of rock documentaries like “The Last Waltz” and “This is Elvis,” focuses on a fictitious heavy metal group on a disastrous tour in the early ’80s. Christopher Guest, Michael McKean and Harry Shearer star as the core members of the daft British band, who are being followed on tour by Reiner as documentarian Marty DiBergi. “This is Spinal Tap” starts at 8 p.m., and tickets are $5 (free for museum members). Details: 919-715-5923 or ncartmuseum.org.