Planet of Serpents was an original comic strip in the pages of the 1976 Dalek annual. Like the other stories in that volume, it featured the trio of Reb Shavron, Mark Seven and Joel Shaw. It was, however, mostly Shavron's story; the two men only showed up on the final panels.
Reb Shavron is on her way back to an ADF base after a solo reconnaissance mission. An unexpected meteor storm damages her ship, forcing her to set down on the extremely dangerous planet of Terroth. There, she encounters the swamp people, who quickly imprison her. They also tie her to a sacrificial altar and offer her up to appease the "great ones". She quickly discovers she's being offered as dinner to the great serpents which populate the planet's underworld.
Swiftly cutting through her bonds, she escapes the caves that house the serpents. Unfortunately, the Daleks have been monitoring the ADF distress channels. They know she crashed planetside, so they've come down to exterminate her. Mark Seven and Joel Shaw have also arrived on the planet. It momentarily appears as if the core ADF leadership are about to lose their lives.
Just as the Daleks are demanding the lives of the ADF agents, the great serpents burrow up through the ground and consume the Daleks. The ADF trio make a mad dash to Shaw's ship, and they're off to the safety of space.
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