This movie takes frames from the last two instalments of the first epic strip story of Marina - Girl of the Sea as seen in issues 22 and 23 of Lady Penelope, and matches it to the dialogue from the Century 21 Mini-album Marina Speaks, featuring the original cast members:

Sylvia Anderson as Marina
David Graham as Aphony
and the First Minister (Barinth in the strip)
and Ray Barrett as Titan