The Professionals (1977)

Private Madness, Public Danger - S1-E1

Plot hole: When Bodie and Doyle arrive at World Chemical Products, they meet some of the senior staff in Mr Harvey's office. Revealing that chief chemical analyst Mr Cummings would be able to test the vending machines for the ADX Poison, Harvey appears to pick up the telephone to talk to Cummings, despite the fact he is stood in the very same office.

Heroes - S1-E5

Plot hole: The scene of old Mr May coming under fire and that of the CI5 back-up squad were filmed outside different houses (although in the same street).

Where the Jungle Ends - S1-E6

Plot hole: When Krivas threatens to shoot Benny, the pistol's slide is locked in the open position, which indicates that the pistol is either out of cartridges, or a cartridge (or cartridge case) has jammed within the pistol and so cannot be fired. This makes any threats to shoot a bluff.

Everest Was Also Conquered - S1-E8

Plot hole: Bodie says that Cowley had ordered him and Doyle to stay away from Turvey before CI5 operative Tony Miller was killed. In fact it was AFTER Miller was assassinated.

Everest Was Also Conquered - S1-E8

Plot hole: It is stated that Susie was pushed from a ninth storey window, yet when Bodie and Doyle investigate room 96, they only appear to be four or five storeys up.

When the Heat Cools Off - S1-E9

Plot hole: One glaringly obvious script blunder is that the murder of Fitch and Parker is supposed to have taken place "six years previously" (in the summer of 1971, the date established the pre-title sequence) yet Haydon has been in prison for "seven years and five months" according to his daughter. This makes no sense, unless the viewer is to assume that the "present day" sections of the story take place in early 1979. (The episode was first broadcast in February 1978).

When the Heat Cools Off - S1-E9

Plot hole: The chronology of this episode makes no sense at all in places. For example, the pre-titles sequence makes it clear that it is the summer of 1971, and Doyle mentions to his sergeant that CI5 is being set up. Yet series creator Brian Clemens' own writer's guide specifically stipulated that the CI5 wasn't even conceived until November 1971.

Long Shot - S1-E11

Plot hole: Surely it would have made more sense for CI5 to have contacted the demolition team at the girl's hideout, instead of dodging crashing materials and great big demolition balls, ready to smash them to pieces at any moment. (However, this would not have made for as exciting a scene as Bodie and Doyle risking their lives to save the female in distress).