Given a sentence, generate a most likely context or previous statement. The previous statement should be relevant to the given statement.

Then he slinks down a wall, head first, mask on.
When she reaches it, he is disappeared.

Someone stands up and swoops in close.
A huge, gray, spiky dragon lies chained on the ground.

Someone runs off, leaving the grinning someone alone with the dragon.
Someone struggles out of the vault and runs to a balustrade.