Serious as a Heart Attack simile
To emphasize that you're extremely serious about what you're saying and not joking around.
A: "No, it can't be! You must be joking!" B: "I'm as serious as a heart attack!"
A: "Are you sure you want to go there all by yourself?" B: "Of course! I'm as serious as a heart attack!"
To think or consider something seriously
To have done something really stupid, grave, and irreparable.
Said when one is absolutely serious or not joking in any way
If you say that someone or something is too hot to handle, you mean that they are too difficult or dangerous to cope with.
When a matter becomes serious, or problematic.
This expression was derived from the serious medical condition when someone has a heart attack. Because this is a horrible, dangerous, and life-threatening event, it is not funny at all. It represents something serious. This expression became popular in the 1960s. People often say this to show that they aren’t joking whatsoever.
To be very wet
Because of forgetting bringing an umbrella, I look like a drowned rat when it rains.