It's beginning to look a lot like fishmen: The Fishmen Of Carpantha

 

This little tale gave me a strong sense of déjà vu.

The Doctor and Liz are amongst the observers aboard a Royal Navy cruiser which is testing out some fancy new depth charges. They pass the test which involves destroying a bit of rock. While everyone celebrates, the Doctor and Liz note some radio interference which they think originates from the nearby S.S. Monitor whose job is to assist other ships navigate the rocky waters of wherever it is the story takes place.

But it turns out the Monitor is offering bad course data, much to the chagrin of various captains whose ships end up in Davy Jones' Locker. Upon investigating, it is discovered that the crew of the Monitor have been knocked out cold and a tape recorder with the bum data is being broadcasted to unsuspecting ships. The Doctor and Liz investigate under waves in a bathyscaphe which is "eaten" by a larger submersible with nasty, big, pointy teeth.

They are taken to the home of the Carpanthans, a race of fishmen who put the Doctor and Liz on trial for the destruction of their city - that rock the depth charge destroyed was no mere rock. Their trial takes place in a courtroom which fortuitously happens to have a stash of emergency gas cutting cylinders. Luckily Liz has a lighter with her - does she smoke Virginia Slims? You've come a long way, baby!

Despite a makeshift flame thrower, our heroic pair are unable to effect an escape. However, the Doctor manages to convince the Carpanthan leader that he will not reveal their presence to the apes on the surface. For this act of kindness, the Doctor and Liz are allowed to leave. Those Carpanthans weren't so bad after all and didn't seem to worship Dagon.

I don't know when this comic was written but it bore more than a passing resemblance to Doctor Who and the Silurians. Fish people under the ocean, reptile people under the ground. The Doctor trying to broker peace between a cold blooded race below and the warm blooded apes on the surface.

Liz is back, although she blurts out "Doctor, I'm scared!" at one point. A little science at the beginning but she's mainly the pretty thing needing the Doctor's help.