The Transformers: Headmasters is a four-part mini-series published in 1987 by Marvel Comics, and set in the same continuity as the regular US Marvel comic. It tells the story of two groups of Transformers led by Fortress Maximus and Scorponok, and their adventures on the planet Nebulos; in the process, it introduces the Headmaster and Targetmaster gimmicks to the storyline. In the Marvel UK Transformers series it was run as a back-up strip alongside the regular stories. The Headmasters plot merged with the ongoing Marvel storyline in Transformers issue #38.