Ac 2 v 29 - Flee Market
0Unlocked After: Sequence 5 - Memory 1: Four to the Floor
You're after two conspirators. Both are at the Santa Maria Assunta, in a restricted area surrounded by a bunch of guards. The way into the restricted area is blocked by four guards, but there is a group of Courtesans just east of them. Hire the Courtesans and order them to distract the guards. Walk past the distracted guards and activate Eagle Vision. The targets are together in the courtyard, and as you can see there are quite a few guards with them.
The conspirators will bolt as soon as they detect you. To make matters worse, both targets can Free-Run. Catching both of them with a boatload of guards after you is no easy task, so your best bet is to run in there and take them out swiftly. They're standing close enough to each other that you can score a nice double kill with the Hidden Blades if you're quick enough. If you only manage to get one of the targets and the other takes off, just keep after him. The memory will be desynchronized if either of the targets gets far enough away from you. - https://www.supercheats.com/guides/assassins-creed-ii/