Firstly, it is important to note that RTTFP is set to Shakespearian pentameter, and that much of the dialogue is a concoction of the Bard’s various famous texts. With “golden-oldie” rock’n’roll songs thrown in for good measure.
We begin with a crew aboard a spaceship, navigating through space. On their travels, they receive a distress signal which leads them to a drifting vessel: aboard is the famous (and eccentric) Scientist Prospero and his daughter Miranda: whom the Ship’s cook takes an instant fancy to (the Captain does as well, although he struggles with such feelings for a much younger girl). After they are welcomed aboard, we discover that they were abandoned there by Prospero’s evil wife… Gloria.
Prospero is working on a miracle wonder drug that will cure any ailment, and grant eternal life to those that drink it. Although it’s hasn’t been tested, the stress of seeing his daughter fallen in love with the Captain drives him to foolhardy impatience. Shortly after he takes the drug, the ship is attacked by a monstrous creature: “Is this a monster I see before me, with tentacles instead of hands?” They only avoid certain death because of Prospero’s trusty robot, Ariel, who forces the monster back with his laser weapon defences. But then someone else turns up… Gloria.
Gloria explains that her intentions in abandoning her husband were good; that she had abandoned Prospero in an attempt to save the human race. It seems that his wonder drug has a nasty side effect – it brings horrors from the user’s subconscious to life. And the multi-tentacle space monster that attacked them was one such creation, from the depths of mad Scientist's mind.
In realisation of this awful truth, Prospero makes peace with Gloria, and charges the Captain to take care of his daughter. He takes the only step he can to end the madness… and ends his own life by jettisoning into space. The crew all sing farewell with “You’d Better Go Now”.