Explaining an mRNA vaccine with Star Wars

There's nothing as relatable as a Star Wars analogy to explain something totally unrelated. Randall Munroe goes back to the original Star Wars movie (now called A New Hope) to show how the newfangled COVID-19 vaccines work, at xkcd.

The various parts of the analogy are broken down at Explain xkcd. You'll learn even more in the discussion at Metafilter. And don't forget to read the hovertext at the comic site.

Image: Randall Munroe/xkcd/CC BY-NC 2.5