Rat in a Trap is a Quest in The Elder Scrolls Online.
Rat in a Trap Bestowal
" During Diplomatic Immunity, the Dragonborn will find out about Esbern, an old friend of Delphine and the only other member of the Blades in Skyrim. Delphine will tell the Dragonborn to go to the Ratway in Riften to find him before the Thalmor do. Thalmor Agents will pop up outside as well, and once the Dragonborn has talked to Esbern, the agents will attack. "