2004 is a lame made for TV prequel to the movie 2010. It's weak premise was an attempt to explain what happened between David Bowman's LSD trip in 2001, and Martin Brody's break from his shark fishing career in 2010.
Unfortunately, just like all other prequels, it created a bunch of plot holes and totally reinvented what the original series was all about. It was also not immune to the cold realities of The Future since humanity is not even close to having the ability to travel to Jupiter.
2004 was eventually canceled, and replaced by another Highlander tv series.