Update: It’s been pulled.
For those of us who prefer not to be blinded with a stark white light when looking at our phones it’s finally happened. Google has implemented Dark Mode in Android Messages.

The update to Android Messages is rolling out from today in version 3.5.048 with the toggle for Dark Mode easy to find in the three dot menu.

Once Dark Mode is enabled, you’ll notice it’s not completely black, but a rather dark grey, with bubbles from your messaging partner in a slightly lighter shade of grey, while your bubble is in Blue. The Blue isn’t ideal, but as a whole, the colour choice is far better than the stark white we’re used to.

The update is heading out today, so if you see a notification for it in Google Play, make sure you try it out.

Update:
We’ve seen the promised land but for some reason it appears that Google has pulled the update. For many users the Dark Mode option has now disappeared, leaving them back in a stark white hellscape. It’s apparently a server side switch, so if you had it, you’ll find it’s likely now gone. Still, it shows Google is working on it and we can’t wait for it to be live again.

https://play.google.com/store/apps/details?id=com.google.android.apps.messaging