…move forward and try to open the grate

You glide forward and peer around the bend. There are two guards that you can see, backs to you. You edge forwards towards the locked grate warily, stealthy as a midnight fox. With a flourish of fingers to enervate your nerves you drew your lock picks, and reaching around through the bars you started to pick the lock.

You are a deft hand with a lock and the sewer locks are not complex locks… well actually… this lock is… a little… more… did they upgrade the locks? They must have. But really. It is complex - and… got it. The lock snikts open and you put away the picks in their magic sheaths. You have magic lock picks.