If you support the Save the Whale campaign and like playing computer games, then Moby Dick will keep you happy for hours!
However, if you like fast, addictive original games then I'd give this one a miss. The theme is a fairly old one. Depth charge the submarines and shoot the helicopters. But there's a twist - if you hit Moby Dick, who is swimming in among the subs - you'll be rammed by a large green ship and sink helplessly to the seabed. You are also supposed to catch the pilots of the helicopters as they parachute down from their doomed craft.
You get five ships per game, and there are three attack waves. In the first, the submarines do not attack, but the choppers drop bombs which you must avoid. In wave two, one sub releases floating mines and in wave three the other submarines release tracking missiles.
I found the game slow, and after a while, a bit monotonous. But if you like depth charge games and want one for your new Commodore 64 then I guess you could do worse than this offering from PSS of Coventry. It's available now and costs £7.95.