Metadata is something that goes on behind the scenes and is rarely of concern to either author or readers of scientific articles. Here I tell a story where it has rather greater exposure. For journals in science and chemistry, each article published has a corresponding metadata record, associated with the persistent identifier of the article and known to most as its DOI. The metadata contains information about the article such as its authors and their affiliations, the title of the article and its abstract, and is submitted to/registered with Crossref – an organisation set up in 1999 on behalf of publishers, libraries, research institutions and funders. Relatively recent additions to Crossref metadata are the citations included in the article, so-called Open Citations. Doing so has helped to create the new area of article metrics, used by e.g. Altmetrics or Dimensions to help identify the impacts that science publications have. Basically, if one article is cited by another, it is making an impact. Many citations of a given article by other articles means a larger impact. Most researchers love to have a high – and of course positive – impact and perhaps for better or worse, academic careers to some extent depend on such impacts.