The Big Bang Theory presented in this episode is neither as entertaining nor as plausible as its TV sequel. Trapped in a lazaretto in the center of the universe a mixed bag of villains and visitors face annihilation as a result of the Doctor's tripping a switch to jettison the fuel that will ignite a second Big Bag. The companions all fail to helpt the situation, either inadvertently or deliberately, and the Doctor is only just able to snatch victory from the jams of destruction with the help of a giant doglike physician who heals lazars by absorbing the disease from them. The story is difficult to follow, and hardly woth the trouble.