Ensign Hildebrandt is an Enterprise-D geologist assigned to the planetary survey team that Wesley Crusher leads in the Selcundi Drema sector.
Hildebrandt appears in Pen Pals. When Riker gives Wesley Crusher his first command responsibility, a mineral survey of the unstable planets of the Selcundi Drema sector, she is one of the specialists chosen for the team, with a background in volcanology.
She works alongside Davies and Alans in the ship's laboratory, analysing why the worlds of the region are tearing themselves apart. The team is older and more experienced than its leader, but Hildebrandt takes his direction without fuss.
The survey finds that deposits of dilithium laid down in unusual lattices are generating the stresses that break up the planets. That discovery allows the Enterprise-D to save Drema IV, the home of Data's young correspondent Sarjenka.