prison key

[mp999]

Hi
can anybody help please in masteries courtyard I can't find the key for the second prison door

[abursch]

What prison are you talking about?
If you mean the key for the Prison of Souls in Immortal Throne you have to go deeper into the map to find it. It is on a boss monster. Check here for the map:
http://www.gamebanshee.com/titanquest/walkthrough/royalchambers.php

[Medea Fleecestealer]

If this is the Ancient King's Wealth side quest, then you'll find one key in the Tsakonian Queens' tomb and the other in the Great Tomb of Aegimius. The Queens' tomb is at the end of the swamp area just before you cross the bridge to enter the big courtyard - keep going left and you'll find it. Aegimius' tomb is in the second part of the complex. Once you've cleared the first part and completed the Impossible Task side quest go to northeast corner and make your way to second part of the complex. Tomb is on the righthand side.