The game proceeds by trick-taking in the conventional way (there are no trumps), but there is a catch. Certain cards are listed as penalty cards, and have assigned penalty values. When a trick is taken which contains any penalty cards, the winner of the trick is penalised by the total number of these penalty points. Penalty points are counted at the end of each hand, and each player's running total of penalty points is adjusted as appropriate.
There is another catch! If one player takes every penalty card in the pack (called 'going for the lot'), he can choose to do one of two things; either zeroise his running penalty total, or double everyone else's.
The penalty cards are :-
Queen of Spades 50 points (hence 'Black Lady') Ace of Spades 40 points Ten of Spades 20 points any picture Heart 10 points (this includes the Ace) all other Hearts face valueThe cards are dealt out evenly among all the players, using standard Whist conventions for rotating dealership and lead. This requires that the number of cards in play is divisible by the number of players, so before any hands are dealt, the pack(s) is/are inspected and the appropriate number of innocuous cards of trivial denomination are extracted and cast aside. By convention the discards will be the lowest Diamonds and Clubs (not Spades, as a low Spade lead is often a devastating attack, so they are significant in the game).
When multiple packs are in use, there are multiple cards of each face. There is a rule to cope with this. When the winning card face in a trick is played multiple times to that trick, the first such card played is the one which takes the trick.
There is one further wrinkle, which gives this game much of its aggression and excitement. After the deal and before the first lead, each player must select three of his dealt cards and pass them covertly to his left-hand neighbour, and then accept three cards from his right-hand neighbour. The selection of the pass-on cards is a science in itself, given issues such as suit distribution, ability to lead through a passed-on danger card, hands which may be suited to going for the lot, and so forth. There is also the problem of disguising your intentions from your left-hand neighbour, especially when going for the lot.
The play proceeds, hand by hand, until the allotted time span (typically the lunch break) has expired. The winner is the player with the smallest running penalty score.