Das Boot - the originals series
 

Here you can watch the original series of "Das Boot" from 1981 in six parts in more than five hours of play.
Very quickly, the inclined viewers realize that the series of content and the characters created profound much more than in the movie aka Directors Cut as shown acu.
https://bs.to/serie/Das-Boot-1981

The series in six parts doesn't seem to be available anywhere. The 5-hour 'Uncut' version is said to be the series without the inter-episode credits.

And yes, we have had many threads on this, and most of us agree that the 5-hour version is much better than the Director's Cut, and way better than the 2-1/2 hour theatrical release.