The "Surgeon's Photograph", the most famous photo allegedly showing the Loch Ness Monster, is published in the Daily Mail (in 1994, it is revealed to be a hoax).

The Loch Ness Monster, known affectionately as Nessie, is a mythical creature in Scottish folklore that is said to inhabit Loch Ness in the Scottish Highlands. It is often described as large, long-necked, and with one or more humps protruding from the water. Popular interest and belief in the creature has varied since it was brought to worldwide attention in 1933. Evidence of its existence is anecdotal, with a number of disputed photographs and sonar readings.

The Daily Mail is a British daily middle-market tabloid conservative newspaper founded in 1896 and published in London. As of 2020, it has the highest circulation of paid newspapers in the UK. Its sister paper The Mail on Sunday was launched in 1982, a Scottish edition was launched in 1947, and an Irish edition in 2006. Content from the paper appears on the MailOnline news website, although the website is managed separately and has its own editor.

April 21 is the 111th day of the year in the Gregorian calendar; 254 days remain until the end of the year.