Ensign Garrovick was a 23rd century Starfleet security officer aboard the USS Enterprise under Captain James T. Kirk. Garrovick's father was the former commander of the USS Farragut.
In 2268, Kirk and Garrovick encountered the same dikironium cloud creature on Argus X that killed his father, and two hundred crew of the Farragut, eleven years earlier. Garrovick sighted the creature but was, however, temporarily paralyzed and unable to shoot it. Kirk blamed Garrovick for his hesitation, a blunder which caused the death of two security officers. (An earlier attack, which did not involve Garrovick, killed a Starfleet Academy friend of Garrovick's, Ensign Rizzo.)
It was later discovered that Garrovick's hesitation was unintentional and that phaser fire would not have harmed the creature. Kirk allowed Garrovick to redeem himself. The two set a trap for the creature, which consisted of a container of red blood and a matter/antimatter bomb. The two beamed back to the Enterprise, moments before the bomb went off, which at the same time, destroyed the cloud creature.
While the character's first name was not established through dialogue, the sign to Garrovick's quarters read: "David Garrovick." The character has appeared in multiple novels and comics, and has variously been given the first name David (Star Trek 2 by James Blish), Stephen (In the Name of Honor by Dayton Ward) and Tom (Debt of Honor comic by Chris Claremont).