From a story standpoint, this starting adventure is great! It has everything a story like this should have, and in play my group had a lot of fun with zany situations that arose.

From a game design perspective, They Came From Beneath the Sea is stellar, and much of that awesomeness is communicated here clearly and succinctly.

As a quickstart or jumpstart, though, this product leaves a bit to be desired:

1. Its description of the combat rules have a glaring omission: weaponry. In fact, nothing is mentioned about any kind of equipment. Does my character have a gun? Does a gun give any Enhancement bonus to damage? These questions aren't answered.
2. Trademarks and favored Stunts should have been listed on the character sheets. Their omission means that players will just not use them. Ever.
3. Sometimes Skills and Attributes are mentioned that do not exist in the game system. Both Insight and Charisma are used in descriptions of example rolls, but I think the writer meant Integrity and Presence.

Maybe if your group also owns the core book, you could answer some of these questions, but if you are only playing from the jumpstart, you're going to have to leave some of these probably exciting game features out of your game.

As an aside, purchase on DriveThruRPG presents two different pdfs. They are identical except for the fact that the first one has "Page XX" instead of actual page numbers. This pdf should just be removed from the package. The second one has all the page numbers.

This is a great jumpstart. Gives you everything you need to run a game and a story that's fun for new and experienced Players.