Mr Jelly was frightened of everything.
In fact, he was terribly, terribly frightened of everything.
The slightest sound would send him running to hide under his bed, shaking and trembling just like a jelly.
Poor Mr Jelly!
The terrible sound frightened Mr Jelly out of his wits.
Quivering with fear, Mr Jelly started opening all the bolts and locks on his door.