Photographing a horsehair worm bursting from the body of a drowning cricket is as difficult as it sounds. But it was a challenge that Anand Varma threw himself into for his first National Geographic story.

“Mindsuckers” in the November issue is all about parasites that enslave their hosts. These barnacles, fungi, and flatworms invade their host’s brain in order to control their behaviors and to advance to the next stage in the parasitic life cycle.

Varma had been thinking of proposing a story on mind-control parasites to the magazine, but hadn’t fully fleshed out the idea when he met with now retired National Geographic photo editor Susan Welchman in October 2011.

When Welchman asked whether Varma had any projects he