The Tex Murphy series had reached its pinnacle with The Pandora Directive. In Overseer we get even better FMVs but the story this time around is kinda lacking. Basically, it's Mean Streets again. You no longer have multiple endings or even different paths to take as in TPD.
Acting is mostly on par with TPD, though it's lacking the massive cast TPD had. Still, there are some great actors like Michael York or Henry Darrow. You still get to choose between Entertainment and Gamer Mode, although there is not such a huge difference to them like in TPD. You can bypass some puzzles in E Mode and get extra points for solving puzzles quickly in G Mode.
The puzzles are your basic Tex Murphy fare with some real mindbenders and many jigsaw letters and photos. Conversations are still played out by selecting one of three options, but those have no real effect on the story for the most time.
A bit on the downside is also the fact that you get a massive cliffhanger at the end of the game that never got resolved in a game. There's still hoping for Project Fedora, though....