As a space geek, I'm shocked I didn't know about this. Two men risk death to save a spacecraft.

From a page in a 1970s book about Mariners 6 and 7.

tl;dr: People literally ran to a rocket that was deflating like a balloon, stopped the leak, and saved a spacecraft worth millions.

Wikipedia says that these two people were named Bill McClure and Jack Beverlin, that they didn't actually enter the rocket as the book says, but rather ran up to it at the risk of being crushed. Still pretty brave. Neither of them are alive today, unfortunately. (Link: https://en.wikipedia.org/wiki/Mariner_6_and_7 )

Sorry for potato quality btw; taken on my phone.