Thorn pauses when she hears the voices and marks the difference sounds. Not enough though...they're talking in low tones, and the echoes around the stones make it hard to make out. There could be more who are silent.
Slowly she edges around the tower more, seeking an old window, or hole, that she can look through to get a better idea of who and what is in this place.
(I'll assume stealth and perception...if you need anything else, let me know.)
Thorn manages to slip around and check all parts of the tower. There are no openings she can reach from the ground. There is a small window built into the stout door, but it is closed. Listening carefully, she determines that there are at least three voices engaged in conversation, two feminine and one male. She catches snatches here and there when voices are raised in excitement:
"Now that's where I found the coins..."
"Coins are all well and good, but I ripped the Phylactery right off the old priests arm, you should have seen the look on his face."
"You couldn't steal candy from a baby..."
"Ran the old fart threw I did"
"Holy symbols did them a fat lot of good"
"...Platinum as well as silver..."
"Faxon was right pleased with the matching scimitars..."
"Leave off, I found..."
"Those silver goblets would be a lot better if you'd found a drop of wine to go in them...tired of water and sour ale..."