Annie, I agree with Tracey, it's a must-see. I take it you haven't been to MGM Studios before? It is definitely worth a visit. What sort of passes do you generally buy?
Fantasmic takes place in a huge amphitheater. The action takes place on an 'island' and in the water surrounding the island - the water is in between the audience and the island.
There are three huge 'screens' of water onto which some of the action is projected - rather like film screens. There are three of these so that each section of the audience can see the same thing whether you are over to the right left or in the middle.
As Tracey has said there is a story line, some amazing pyrotechnics, music and stunts and it's loaded with characters. To tell you too much about it would be a shame - as with many Disney attractions it's the element of the unexpected that sets them above the rest.
Since it is included in park entry, I'm sure you and Mr D would enjoy otherattractions in MGM like the Great Movie Ride, the Backlot tour, the Indiana Jones Stunt Show and the Animation Tour and I KNOW you'd enjoy the Muppets 3D show - none of these are thrill rides so Darryl will be okay with these.