Goofs

Although it is supposed to be night when the second victim is killed (darkness can be seen through the windows), it is clearly broad daylight during the exterior search scenes. Vera even mentions it is 'spooky at night'. These scenes were presumably filmed day-for-night, meaning they would be filtered during the editing process to give the impression of darkness. However, the filter was never added.

After the third death, a shot of the Indian figures shows three broken ones (as expected) and eight intact ones, for a total of 11.

During Raven (Aznavour)'s performance of Dance in the Old Fashioned Way, Hugh Lombard (Oliver Reed) is alternately shown sitting and reading a magazine, to standing in front of the staircase, giving a thumbs up. This was an alternate shot taken from the previous scene, when he gives Raven a thumbs up after his performance of 'Ten Little Indians'.

The recorded accusation refers to Lombard's "victim" as Jennifer Hayes, but later, in the milk-drinking scene, Lombard refers to her as Carol.

After Michel is poisoned, the killer breaks the statue at the waist. After Elsa is strangled, the killer breaks the statue at the shoulder. After General Salvé is stabbed, the remaining guests gather around the table on which the statues are placed. The film then cuts to an overhead shot showing two statues broken at the ankle and one broken at the waist. In the next shot, the correct statues are back, but the statue broken at the waist is now in a different position.

A reference is made to the last survivor being locked away in an asylum (as they would be presumed to have killed the others). The story takes place in Iran, where the death penalty was (and still is) in effect.

When the Doctor and the Judge make their deal in the billiard room, the Doctor tries to extinguish a match which is no longer burning.

Grammatical error by the character Raven when reciting the famous nursery rhyme. It should be 'He went and HANGED himself' not 'hung himself' as he recites.

The international print contains the misspelled credit "Music composed an conducted by Bruno Nicolai".

Based on the play by Agatha Christie rather than the novel as credited here.

When Aznavour sings "The Old Fashioned Wayl", he magically has drums accompanying him, yet it's supposed to be only him and the piano.

When the judge takes his final shot on the billiard table, there is only one ball left to pot, yet the audio clearly sounds as though the ball being potted makes contact with another ball (in addition to the cue ball).