Walk this way

It’s 1986. Rap music is explosive and on the rise but still misunderstood and barely represented in the mainstream. The leading innovators are Run-DMC, a trio from Queens who sport black leather jackets and unlaced Adidas sneakers. Two albums into their career, Joseph “Run” Simmons, Darryl “DMC” McDaniels and Jason “Jam Master Jay” Mizell are already minor stars and musical revolutionaries. For their third album, producer Rick Rubin, a 22-year-old white kid from New York University, comes up with a crazy idea: He recruits Steven Tyler and Joe Perry, the leaders of the down-and-out arena-rock group Aerosmith, to collaborate with Run-DMC on a new version of their 1970s staple “Walk This Way.”