The game is a variant on the old-fashioned wire loop electric game popular at fun-fairs and the flammer stores around the United States. It consists of an "operating table", lithographed with a comic likeness of a patient (nicknamed "Cavity Sam") with a large, red light-bulb for his nose. In the surface are a number of openings, which reveal fictional and humorously-named ailments made of white plastic. To work, the game requires two AA batteries.
The comic likeness of the patient is known for having "helmet hair", a hairstyle that became popular in the 1990s.
There are two sets of cards: Doctor and Specialist cards. The Specialist cards are dealt out evenly amongst the players at the beginning of the game.
Players take turns to pick Doctor cards, which offer a cash payment for removing a particular ailment, using a pair of tweezers connected with wire to the board. If a player successfully removes the ailment they collect the amount shown on their card. However, if the tweezers touch the metal edge of the opening during the attempt (closing the circuit), a buzzer sounds, the patient's nose lights up red, and the player loses their turn. The player holding the Specialist card for that piece then has a try, getting double the fee if they succeed. Since there are times when the player drawing a certain Doctor card also holds the matching Specialist card, s/he can be tempted to purposely botch the first attempt, in order to succeed on the second try, for double value.
The winner is the player with the most money after all the pieces have been extracted.
The game can be difficult, due to the shapes of the plastic ailments, and the fact the openings are scarcely larger than the ailments themselves.
In 2003, Milton Bradley allowed fans a chance to vote on a new piece to be added to the original game. The people were given three choices, and could make their selection via the company's official website or by phone (866-SAM-VOTE) for a chance to win a $5,000 shopping spree
Voting ended on the 31st of December, and the winning piece (beating out tennis elbow and growling stomach) made its debut in October 2004:
Aside from the traditional board game version, Milton Bradley also produced a hand-held version, a brain surgery version requiring the player to pull pieces out of a wisecracking Cavity Sam's head, and a PC game produced in 1998.
In May 2004, a Shrek 2 version of the game was released.
In December 2006, a Spider-Man version was released, in which the player operates on the Marvel comic hero, Spider-Man.
In early 2007, a SpongeBob SquarePants version was introduced, featuring game pieces such as a "shoehorn" and a "Krabby Patty pleasure center". Based on the Nickelodeon TV series by the same name.
2007 also saw the release of a Simpsons version of the game, featuring a talking Homer Simpson being operated on by doctors Julius Hibbert and Nick Riviera. Items in the game include Bowler's Thumb, Foot in Mouth, and Rubber Neck. When a player misses, the Homer figure screams or says one of his trademark lines
Later in 2007, Hasbro released a different version of the original game called, "OPERATION Rescue Kit". Here you play four different timed games with three skill levels. Each skill level reduces the starting amount of time. Cavity Sam now has a heart monitor, and you can even pump oxygen into him to gain more time.
A Doctor Who version of the game was released in Great Britain, where players get to "operate" on a Dalek in order to (from the product description) "make it strong enough to take over the world. But be careful... if you damage it it'll quickly tell you with one of its terrifying phrases! Whether it's the Targeting Sensor that you need to operate on, or the Manipulator Arm, you'll need a steady hand and nerves of steel!"