I loved Deadline. I didn't get too far on my own in solving the mystery, but I spent a long time exploring and having fun.
This is a mystery game, where a man has been found dead, and you have to investigate the house and people in it. Everyone walks around, has scripted events, etc. I asked everyone about everyone else, examined the crime scene, etc.
I missed an important verb which is listed in the manual, and which you are supposed to know from the beginning; typing ANALYZE or ANALYZE [SOMETHING] FOR [SOMETHING] sends someone to analyze stuff for you.
Now so many other games make sense. For instance, Jon Ingold's Make It Good really borrows a lot from this game, and now I realize it must have been an intentional homage, meant to help and mislead the experienced gamer (which I wasn't when I played it).
Deadline was an early experiment in timed and scripted events, as well as extensive conversation.. Games like Varicella or Pytho's Mask may not have existed without this one.
It' s also very hard, in unfair ways. I recommend eventually settling on a walkthrough. Like the great novels of the 1600's-1800's, it was designed to last for a long period of time in the absence of other material.