The Interrogation and Resist Interrogation skills are abstractions and roll-ups of all the skills and training necessary to read people or effectively gain information from them against their will (or conversely, to prevent the same). This also governs reading people in normal conversation and gleaning hidden meaning from their words. Interrogation can be used in two ways, depending on the current circumstances of the target. Your effective use of these skills will be offset by the target's ability to Resist them.
This facet of the skill is usable once per day (refreshes at dawn) per level of the Interrogation Skill. After at least 30 seconds in conversation with a person who is *not* at your mercy, the "Sense Motive" skill may be invoked. When it is invoked, the target of the skill must reveal all the applicable general tells associated with the conversation (described below). You may use Sense Motive on multiple targets in the same conversation, but you must spend one use for each one. If the conversation is longer than 10 minutes, only the most recent 10 minutes is covered, but SM may be used multiple times in a single conversation. However, if a use is Blocked (with "Block Sense Motive"), that part of conversation cannot be SM'd again.
For each level of Interrogation (minus the target's levels of Resist Interrogation), the Interrogator may ask for a specific tell to be explained (i.e. what statement/info was relevant).
If the target has at least level 2 of Interrogation (not Resist), they know when someone tries to read them by using Sense Motive, otherwise they notice nothing. A Character need not be aware of a Sense Motive attempt to use "Block Sense Motive" - such use is at the Player's discretion.
Each level of Resist Interrogation grants one use of Block Sense Motive per day (refreshes at Dawn), used as described above.
If you have a target completely at your mercy, which is to say restrained and unable to leave or defend themselves, then you may use the At Mercy Interrogation facet of the Interrogation skill. This involves an Interrogation skill test, modified by the target's Resistance. A target's Resistance rating is equal to a character's "Resist Interrogation" level, plus 1 point for every 3 *current* Stamina Points they have (we presume that the target will be "worked over" to lower this before Interrogation proper begins, but YMMV). Prior to testing, white stones should be *removed* from the testing bag equal to the target's Resistance rating. This, and the test itself, should be performed by the *target*, before interrogation begins, without revealing the results to the Interrogator. An At Mercy interrogation may include one Assistant (the Assistance should be stated before hand, and the Target should automatically make two hidden draws, breaking if either is white).
Now the Players should RP the interrogation for 30 minutes. If the Test drew a white stone, the target will "give up" at some appropriate point during or at the end of this period by stating "Forsooth: I'm Broken" (they may also do so at any time even if the Test failed, at the Player's discretion). If the target remains unbroken, the process may begin again after the 30 minute cycle time.
When the target breaks, the Interrogator may ask up to 5 questions of the subject, all of which much be answered truthfully (and fully) to the best of the character's knowledge.
There is no limit to the amount of times you may perform an At Mercy Interrogation on a subject, however at the discretion of the GMs, extended interrogation may be ruled to constitute a systemic mortal wound (organ failure).
P.S. Yes, we know it doesn't really work this way - welcome to Exciting Cinematic Adventure!