It is the year 2000 and the world has been overcome by a bunch of out-of-town aliens who have set up their HO on top of the CRL skyscraper (bit of wishful thinking here). Your task is to climb the skyscraper (inside - this isn't a Kong game!) and destroy their heavily fortified base atop it.
The CRL skyscraper is shown with an arrow pointing out where you are at present. As soon as the game proper starts you realise that what we have here is a 'Panic' game where holes must be dug for monsters to fall into and where they can be banged on the head and sent to their death. Depending on the type of monster you must shove them through one, two or even three floors.
What makes this game different from most 'Panic' types, is that most of the ladders have a door at their top, and, while shut, these doors keep the monsters at bay or trapped between two levels of the six on each screen. Opening a door will reveal a monster ready to pounce down the ladder on to you. This means a strategy for killing them off has to be worked out before a door is opened.Subsequent screens are varied, with ladder positions changing and the numbers of monsters increasing, their speed as well. More of them become white and then purple.. Your man can dig holes and fill them, he may also jump down one level through a hole.