Technical Ford Trunk Lock Problem

I inserted key into the trunk lock on my 58 Ford Fairlane and the key and lock spin in a circle and will not unlock. Will spin just as easily clockwise or counter-clockwise.
I have never had a problem with the trunk latch and the SOB worked fine literally 5 minutes before!

Any thoughts would be greatly apprciated1

 

something broke or fell off. take out back seat to get a look at backside of lock and go from there

 

Will the tumbler come out with the key?

 

Tumbler stays in the latch.
I was hoping the problem was in the lock, but the pot metal arm off the lock shaft is broke.
I will see if I can find one, or fab something up.
Thanks.