T'Pol

Commander T'Pol was a noted Starfleet officer in the 22nd century; the first Vulcan to serve aboard an Earth ship for any substantial amount of time, and was a member of Jonathan Archer's senior crew on the Enterprise.

Early life
T'Pol was born on in 2088. 

In the 2130s, T'Pol was undergoing secret security training and graduated in 2135. One of her first missions was to retrieve seven Ageron agents; after successfully retrieving six of the agents, one of the men named Menos managed to escape. On Risa, T'Pol killed a man named Jossen. As a result of thinking she had murdered an innocent man, T'Pol returned to Vulcan and resigned her position, and eventually went to P'Jem to seek guidance. On P'Jem, T'Pol underwent the obsolete Fullara ritual which suppressed the memory and emotions of the event. 

Another mission T'Pol undertook as a V'Shar agent was also in 2135, to the Vulcan outpost settlement on Trilan. There, she and a team of five others pursued a group of Fri'slen, cannibalistic humanoids carrying a blood-borne mutagen who were terrorizing the outpost. The squad was led by, and also included Eskren, Vekk'r, Ych'a and Yekda. Only T'Pol, Denak and Ych'a survived this mission. 

T'Pol joined the Vulcan Science Directorate circa 2136.

She was assigned to the Vulcan science ship VS where she served as the deputy science officer under Captain in 2148. After a year of serving aboard the ship, she was transferred to the diplomatic branch. 

By 2149, T'Pol had risen to be assigned to the Vulcan Consulate on Earth as Ambassador Soval's aide. 

On Enterprise
In April 2151, when Captain Jonathan Archer and the Enterprise (NX-01) set out to return Klaang to Qo'noS, T'Pol was assigned to the Enterprise as an observer. T'Pol proved essential in the mission, as her knowledge and Vulcan star charts allowed the Enterprise to complete her mission. Captain Archer requested she remain aboard as science officer and first officer. 

When P'Jem was destroyed by the Andorians later in 2151, T'Pol was recalled from the Enterprise by the Vulcan High Command; she went on a last mission to Coridan III with Captain Archer in a shuttlepod. The shuttlepod was shot down and captured by a rebel faction, but they were rescued by the Andorians. Following this event, T'Pol's transfer was revoked. 

A few weeks later, while the Enterprise was exploring the Arachnid Nebula, the starship encountered the Vulcan ship Vahklas. On board was a group of V'tosh ka'tur (Vulcans without logic), led by Captain Tavin. Although initially wary, Subcommander T'Pol eventually showed some curiosity about their unorthodox philosophy and agreed to a mind meld with Tavin's first officer, Tolaris. However, when she asked him to stop the meld, he refused and she had to use force to escape. It was later revealed that T'Pol contracted Pa'nar's Syndrome during the meld. 

In 2152, T'Pol's memories of her mission to apprehend the Ageron fugitives were reawakened, and she set out to capture Menos. With Captain Archer's help, she succeeded in doing so. 

Later the same year, her time aboard an Earth ship left her with a "Human accent," according to Ambassador Soval. 

When the Xindi attacked Earth in 2153, Enterprise was recalled to Earth by Admiral Maxwell Forrest. Captain Archer persuaded Forrest to go after the Xindi, but the Vulcans did not want T'Pol to go on the mission. T'Pol resigned her commission and boarded the Enterprise as it headed to the Delphic Expanse. 

While in the Expanse, Enterprise received a distress call from the Vulcan ship VS. On boarding the Selaya, they found that the crew of 140 had been driven insane as a result of poisoning with Trellium-D, which was a neural toxin for Vulcans. T'Pol was also affected by the poisoning, but was treated and recovered. 

After becoming addicted to Trellium-D, T'Pol and Commander Charles Tucker III had a sexual encounter in late 2153. 

The year 2154 saw T'Pol accept a Starfleet commission at the rank of Commander, after Enterprise returned from her mission into the Delphic Expanse.

In 2155, during the Earth-Romulan War, Captain Archer sent T'Pol home to Vulcan, in order to convince T'Pau to bring Vulcan fully into the war. T'Pol was unsuccessful in convincing T'Pau, but she did begin an investigation into Kuvak's secretive arms shipments. T'Pol returned to the Enterprise before she could finish the investigation, so she left it in the hands of Charles Tucker III, Ych'a, Denak, and Terix.