I was playing a morally-bankrupt rogue in an Advanced Dungeons and Dragons campaign. The rest of the party included an evil schizophrenic wizard, a very annoying lawful good cleric (Ed: lawful good is one of the nine alignments available in Advanced Dungeons and Dragons.), and a dumb and gullible fighter. The evil wizard in the party and I often teamed to accomplish our nefarious goals. One night, we were all camped outside a large (and treasure-rich) city when the sky took on a sickly hue and a rain of deadly poison descended over the land. It was the effects of an ungodly-powerful spell.
We all woke up, as we were taking damage from the outer fringes of the spell and hearing the screams of the dying from the city. As everyone wondered what was going on, two words popped into our (me and the player controlling the wizard) heads: looting spree. We then, using the wizard's magic, became invisible and teleported into the city, where we proceeded to loot the now-unoccupied magic store. Then we teleported to another distant city to appraise and sell the loot. Afterwards, me being the sneaky rogue, came up with a fabricated story to tell the others. We finally teleported back and rejoined them at a huge mournful funeral.
Of course they were very suspicious about our absence, wondering where we went. This is where luck kept one evil rogue and one evil wizard from getting lynched. I told a long story of how we had teleported to the Elvish capital to get information about the spell and that we had done nothing bad or illegal at all. I rolled for my Bluff check and got a natural 20! (Ed: A natural 20 means that the die roll was 20 before any modifiers are applied, as opposed to getting 20 with modifiers. Not only is this a good roll, but it often confers special benefits, such as a critical hit.) No one else was able to beat that. However, the cleric, my nemesis, wasn't there to hear my rousing performance. When she returned later, I had to make another Bluff check as she asked where the wizard and I had went also. I rolled a natural 1 (critical failure). I cursed my luck. Then she rolled, and also got a 1. Fortunately, my Bluff skill was around 8 points higher than her Sense Motive skill. Though I did a really horrible job of lying, she did an even worse job of trying to detect my lie. This was my luckiest moment, since if I had failed I would most likely have had to roll up a new character within minutes.