The description from Board Game Geek is as follows:
Liar's Dice is a dice game where each player is given five dice and cup to roll and hide them with. Players make successively higher declarations regarding the results of all the dice remaining in the game, e.g. "there are ten sixes". However, someone can always contest the bid. When that happens, all the dice are revealed and either the bidder or the caller loses dice, depending on who was correct. The last player with dice is the winner.
Despite all of the dice rolling, this bluffing game is largely about reading the room. And the more players involved, the less important the dice rolling becomes. It should be noted that a lot of folks don't take full advantage of their turn by revealing some of their dice and re-rolling the remainder. This is especially effective if you have at least four dice and are revealing two of them, I have found. Our buddy Ernie has two sets of this game which are combined so that a massive game of Liar's Dice can be run with a dozen players. Great fun!