Ref. To sherlock
To exit a party / wedding before it ends and to put your long coat on in a cool way as you do it.

A reference to Sherlock Holmes, the main character in a series of mysteries by Sir Arthur Conan Doyle. The detective often solved cases by noting miniscule evidence. The phrase is often used sarcastically when someone points out the obvious. However, it can also be used seriously when someone solves a mystery.

To have survived an impossible situation in which you are presumed dead.