The Mystery of Number 47

{{Short description|1912 novel}}

{{Use dmy dates|date=April 2022}}

{{infobox book

| name = The Mystery of Number 47

| translator =

| image =File:The Mystery of Number 47.jpg

| caption = American first edition

| author = J. Storer Clouston

| title_orig = His First Offence

| illustrator =

| cover_artist =

| country = United Kingdom

| language = English

| series =

| genre = Comedy mystery

| publisher = Mills & Boon (UK)
Moffat, Yard & Co. (US)

| release_date = 1912

| english_release_date =

| media_type = Print

| pages =

| isbn =

| preceded_by =

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}}

The Mystery of Number 47 is a 1912 comedy mystery thriller novel by the British writer J. Storer Clouston. Living in a quiet suburb of London and writing detective novels under an assumed name, Irwin Molyneux is suddenly drawn into a real-life case when he is sought by Scotland Yard for the murder of his wife due to a series of misunderstandings. It was originally published in London by Mills & Boon under the title His First Offence.