The main objective of the present study is to investigate whether there is a difference in comprehension between two groups of Swedish L2 learners of English when they are faced with idioms in either a written context or in an audio-visual context. The investigation was performed at a Swedish upper secondary school. The subjects of the investigation are two different groups, where group 1 consists of 21 subjects and group 2 of 26 subjects. To one group, the idioms were presented in a written context, which is a transcribed version of the audio-visual context to which the second group was subjected. The results of the study are statistically confirmed, which means that they are generalizable to any two similar sets of students taking the same two tests and they show that there is a difference in comprehension for L2 learners if they are presented with idioms in an audio-visual context in comparison to when they are presented with a written context. This difference suggests that the comprehension of L2 idioms can be strengthened when the idioms are presented in an audio-visual context.