Edwin is Donovan Grand Smith's grandson. Like Ben, Edwin is brave and resourceful: when facing the Bermuda Triangle Aliens, Edwin displayed virtually no fear, and even saved Ben by lancing one of the aliens with an oar. Edwin is also rather mischievous, much like Ben. For example, although it was his grandfather's prized possession, Edwin took the Undersea Manta Ray out for a joy ride. Despite all of the above, Donovan strives to make Edwin more like himself. He also was quick to deduce from Ben's absences and the simultaneous appearance of alien rescuers that these and Ben were one and the same.

Edwin played a critical role in defeating the aliens of the Bermuda Triangle by wiring the hotel's energy source to cause an implosion, at the expense of the hotel.