How to extract a particular directory from a multi-part RAR using unrar CLI

I've had this very problem before and here is the answer.

unrar x filename.part1.rar

I just tried this by creating a split solid RAR archive, then deleting all parts except two from the middle. Some files spanned more than these parts, whereas others were contained in just these two. I was successfully able to extract the latter files.

So basically if you download just the parts that you know for sure contain the complete video, you should have no problems extracting it.

Note that if you see Filename --> in one of the parts it means that file is continued in the next part of the archive. If you attempt to extract it without having the subsequent archive part RAR will complain with "You need to have the following volume to continue extraction: <volume name>".

If on the other hand you see Filename <-- in one of the parts it means that file is continued from a previous part of the archive. If you attempt to extract it without having the previous archive part RAR will complain with "You need to start extraction from a previous volume to unpack <filename>".