The study looked at how a parasite called Trypanosoma brucei moves through tissues by studying its flagellum, a whip-like structure. By using a special imaging technique, the researchers found that the parasite's body can change shape in response to the flagellum's movements. This flexibility helps the parasite squeeze through tight spaces in the body. The researchers proposed a new idea on how the flagellum's motion is linked to the parasite's ability to change shape, which helps it move through barriers in the body.