A 1970 Andy Warhol poster, a collection of Pewabic pottery and a working script of The Wizard of Oz.

ANTIQUES ROADSHOW is in Detroit, Michigan, where host Mark L. Walberg and appraiser Laura Woolley head to the Motown Museum to discuss memorabilia that hits a high note with collectors. Highlights include a 1970 Andy Warhol poster the guest bought at his campus bookstore for around 10 dollars and had signed by Warhol himself; an early 20th-century collection of locally crafted Pewabic pottery; and a working script of The Wizard of Oz, used on set by Bert Lahr, fondly known as the “Cowardly Lion,” that is appraised for $150,000.