Pretty much as it says! There are a number of reasons you might want to engage an enemy that has already been exhausted, Aloof enemies, whilst using Machete, etc. But, the only reference I can see to this is in the distinction of being engaged with a *ready* enemy, which suggests you can be engaged by an exhausted enemy, just feels a bit weird to me...

Any thoughts?

Oh, and please don't just say "yes, obviously, d'uh" or something, please show your working!

http://arkhamdb.com/rules#Engage_Action

" To engage an enemy at the same location (for example, this could be done to engage an exhausted enemy, an aloof enemy, or an enemy engaged with another investigator) , an investigator places the chosen enemy in his or her threat area. The investigator and the enemy are now engaged."

Thank you! Me and my compadre were scrutinising the rules reference book mid game and could not see that sentence for some reason... A long day, followed by a harrowing arcane experience will do that to you I guess!

I'm going to have a lie down in a darkened room now...