When Archangel comes to String's house to ask for his help you can see his eye through his eye patch.
At the start of the episode, when the men open the crate containing the Mongoose and tilt the lid towards the camera, you can see that "Mongoose" is misspelled. It actually says "Moongoose."
When Stern is demonstrating the freshly stolen Mongoose near the start of the story, the explosions are all stock footage of previously used sequences. In fact, in one sequence, as a car is blown up, if you look towards the bottom left hand corner of the picture, you can see the blades of a helicopter, that was in the original sequence that the footage is taken from!
(String, explaining that he had to destroy the Mongoose, but kills Karl in the process) String: I had to stop them, you know that. Annie: I understand.
(Larson is telling Karl how he took care of Dominic) Larson: You should've seen it. He went off that cliff like Evil Knievel trying to jump the Snake River... except Evil lived.
With the third season, spelling of the Firm was changed to being spelt as "the F.I.R.M.", in initials, which is proven on-screen by a F.I.R.M. card that Slade holds up when he plans to contact them. (Quite what these initials stood for was never explained or hinted at).
S 4 : Ep 24
Aired 8/7/87 (46:56)
S 4 : Ep 23
Aired 7/31/87 (46:54)
S 4 : Ep 22
Aired 7/24/87 (46:55)
S 4 : Ep 21
Aired 7/17/87 (46:55)
User Score: 1865
User Score: 188
User Score: 165
User Score: 104
User Score: 27
User Score: 26
User Score: 17
User Score: 15
User Score: 15
User Score: 14