The purpose of the present study is to find out the extent to which the real spoken language is reflected in TV series in terms of vocabulary. In accordance with this purpose, a corpus, named as the British TV Series Corpus (BTSC) was compiled for the present study using two British TV series, Sherlock and Doctor Who, and this corpus was compared to the spoken part of the British National Corpus (BNC), more than 40% of which was compiled from naturally occurring speech in order to find out whether there is a relationship between two corpora. The results showed that the TV series corpus covered the 98.54% of the most frequent lemmas in the spoken part of the British National Corpus, so the language used in TV series reflects the language spoken in the real life in terms of the vocabulary items and their frequency. Accordingly, it can be claimed that TV series can be used as effective in-class and extra-curricular materials for teaching vocabulary and speaking and listening skills.