I’d posted about “20 Days in Mariupol” last year, which is an award-winning documentary about the assault on Mariupol. Human Rights Watch has their own video out, which to me looks like a summary of the investigation that they’d done about Mariupol, in conjunction with a couple other organizations I hadn’t heard of. Some overlap of content, of course, but presented in a fairly concise and more “news program” type approach.

It’s only about 22 minutes long, so not as much of a time commitment as “20 Days” is. Some graphic content, as you would expect from eye witness accounts and video.

I did a little additional looking and this appears to be the main page for their reporting, from which the above video became a part/summary:
https://www.hrw.org/feature/russia-ukraine-war-mariupol
The page has some nice images of Mariupol before the war. Makes what happened all the worse.