Hal Wyeth was a Human male who served in Starfleet in the mid-23rd century. By 2254 he had achieved the rank of Commodore and had been the commanding officer of Starbase 13, in the Marrat Nebula, for some time.

In that year Wyeth oversaw Starfleet's Project Pharos, a scheme to build an interstellar lighthouse on a planet in the Nebula to help regulate local traffic. The plan saw considerable opposition from the local criminal groups, who banded together to launch attacks on Starbase 13 in protest.

The USS Enterprise was dispatched to the area, and arrived in time to drive off the latest brigand attack and render aid to the Starbase. Wyeth filled Captain Christopher Pike in on the situation, and the most recent news; that contact had been lost with Pharos. Pike took the Enterprise to investigate.

En route Pike contacted Wyeth to report his status; Wyeth warned Pike that, while in the Nebula, Pike should be vigilant, to "always expect the unexpected". Once the transmission closed Lieutenant Jose Tyler commented that after so long on the front line "Ol' Wyeth" seemed to be getting jumpy. Pike conceded the possibility, but suggested to Tyler that Wyeth's local knowledge might be an invaluable resource. As it happens the Enterprise did indeed encounter the unexpected, a Klingon attack on Pharos. (EV comic: "The Fires of Pharos")

Although Wyeth was addressed as a commodore, the uniform he wore had shoulder braid used in TOS and EV comics representing the rank of captain, with two solid stripes around a broken stripe in between