It's one thing to sit down to a perfectly nice three-course meal, surrounded by your close friends and loved ones. It's quite another thing to sit down to the same meal surrounded not only by your friends, but by a slew of shifty-eyed murder suspects. Such is the situation guests find themselves in at Mystery Café, America's original murder mystery dinner theater.

Like the perfect crime, the idea behind Mystery Café is equal parts simple and brilliant. The line between dinner guest and audience member is blurred as a crew of potential murders attempts to evade suspicion by serving a delicious three-course meal. All the while, guests answer a series of questions based on their observations; at the end of the meal, the individual with the most correct answers wins.

Popular though it may be, the mystery dinner is only one of several gut-busting comedy acts sponsored by Mystery Café. Another is ComedySportz Boston, a lightning-fast improv competition in which two teams vie for points by playing in a series of goofy improv games. Regularly held at the Davis Square Theatre in Somerville, ComedySportz has all the elements you'd look for in a more traditional sport: breakneck speed, a rowdy audience, and a referee who governs the action and decides if the losers get to live.