No, luckily for Mister Jimgrim it is not a trick.

Otherwise he would have shared the fate today of Bedreddin Shah the constable.

The trap was all ready for him.
With the inquisitive and really clever out of the way there is nothing to be feared.

Now--pardon me, Captain Ali Mirza, but that letter you received just now; would you like to show it to me ?" "Why ?" Grim demanded, frowning, and bridling all over.
"Hee-hee! For the sake of reciprocity.

I have told you my secret.