Jim Jacobs (born October 7, 1942) is an American actor, composer, lyricist, and writer for the theatre, long associated with the Chicago theater scene. Jacobs is best known for creating the book, storyline, characters, lyrics for the 1971 musical Grease with Warren Casey. Grease would later be adapted into the film Grease in 1978, which would become one of the most successful film adaptations of a musical in history in terms of gross revenue adjusted for inflation. Biography Career Jacobs was born on October 7, 1942 in Chicago, Illinois to Harold, a factory foreman, and Norma (Mathison) Jacobs. Jacobs attended Taft High School, during which time he played guitar and sang with a band called DDT & the Dynamiters. When he was 11, his idol was Bill Haley, but when he was fourteen it was Elvis Presley. He also cites Buddy Holly, Little Richard, and Jerry Lee Lewis as influences. When he was a teenager, he would imitate playing a guitar with a broomstick. He eventually convinced his parents to pay for guitar lessons. After four lessons, he quit and decided to buy a guitar book and teach himself. From this, he found a simple chord structure: C, A minor, F, G7—this would later be Those Magic Changes featured in Grease. While continuing to learn guitar he also was in a band, with guitarist Terry Kath in his late teenage years. When he was 19, his parents convinced him that he shouldn't go to college, and instead ended up working at a factory packing ink. After a year working at the factory, he decided to quit. In 1963, he became involved with a local theatre group that included Warren Casey, The Chicago Playwrights Center (at that time it was called Hull House Playwrights Center) run by artistic director Robert Sickinger. For the next five years he appeared in more than fifty theatrical productions in the Chicago area, working with such people as The Second City founder Paul Sills, while earning a living as an advertising copywriter. He also landed a small role in the 1969 film Medium Cool. Jacobs' Broadway acting debut was in a 1970 revival of the play No Place to be Somebody, followed by the national tour. Grease In the second half of the 1960's, he and Casey were collaborating on a play about high school life during the golden age of rock 'n' roll in the