There have been 12 Doctor Who episodes that have introduced each of the Doctor's incarnations. Let's rate all of them, including Peter Capaldi's first episode, "Deep Breath," IN ORDER!
What makes a good Doctor introduction story? It's not the same as asking what makes a good Doctor Who episode in general.
When a new Doctor gets his very first story, it needs to do a lot of things -- show us how this new Doctor is different from his predecessor, reintroduce the Doctor/companion dynamic, satisfy old fans and probably act as a jumping-on point for new fans as well. These things are universally true, unless you are William Hartnell, in which case you have the added task of selling the show to audiences for the very first time. No pressure.
In rewatching every intro story, it's become clear just how difficult it is to craft a truly outstanding first Doctor episode. There are basically four categories in terms of quality: bad, eh, good, and great. Each, it happily turns out, has an even three episodes.
So let's look back (and forward) at all the Doctors' first stories, from the worst of the worst to the best of the best.
And feel free to argue with me in the comments or on Twitter at @syfywire, because, frankly, that's the best part of making this list.