Captain Tucker is one of the best aliens featured on LIS, particularly because he befriended Will and did the nipper a favor by disillusioning him to the ways of piracy before leaving last time.
This episode is a terrific adventure.
But what's with the rope that binds Tucker? Once Will cuts the ropes around Tucker's wrists, the ropes around his ankles slip off with no attention.
Why does Will get mixed up with these aliens all the time, and why do these aliens take such a liking to the boy? It's because Will is inquisitive, adventurous and polite, and in the end loyal even to those who aren't so nice to start. He soaks up stories and adventure like a sponge, now becoming a pirate then becoming an Arabian thief, even in escape back to his family trying hard to help even those who first captured him.