This might have been a British show, but I can't be sure. The story has this old guy in it who if I remember correctly was an extra-terrestrial. He teaches some kids how to fend off these swamp-monster (sea-weedie) type creatures, by "focusing light" which then emanates from their foreheads in a kind of rotating white line.
In one scene I remember the kids were stuck with these creatures in caverns which where underneath the ocean. They "jumped up" into the ceiling of a cavern which kind of behaved like quicksand in reverse: the cavern ceiling sucked them through and they emerged on the floor of the ocean near a beach.
In the final episode, the old guy dies, and the kids watch him get taken into space also by some kind of white light.
I remember the material being quite dark for a kids show...
In one scene I remember the kids were stuck with these creatures in caverns which where underneath the ocean. They "jumped up" into the ceiling of a cavern which kind of behaved like quicksand in reverse: the cavern ceiling sucked them through and they emerged on the floor of the ocean near a beach.
In the final episode, the old guy dies, and the kids watch him get taken into space also by some kind of white light.
I remember the material being quite dark for a kids show...