In the mirror universe, T'Pol was the Starfleet officer, with the rank of Lieutenant Commander that served as science officer on the ISS Enterprise NX-01. T'Pol resented being thought of as a slave, and was often voicing her opinion whether she had been asked to, or not.
T'Pol was on duty, in command of the bridge when Commander Jonathan Archer, the first officer of the ISS Enterprise NX-01, staged a mutiny and removed Captain Maximilian Forrest from command. When she stated to Commander Archer that there had been no communique had come through as he suggested, he told her it had been on a private channel. T'Pol would then request to see the orders, only to be told by Commander Archer that she'd be allowed to do so -- eventually. (ENT: "In a Mirror, Darkly")
T'Pol reluctantly complied with Commander Archer's orders, and, while under armed escort of a MACO officer, retrieved the Suliban cloaking device from cargo bay two, and then took it to engineering were she would help chief engineer Tucker install it. (ENT: "In a Mirror, Darkly")
In a meeting with Captain Archer in his ready room, T'Pol read, and then mentioned that the orders Archer apparently received appeared to be authentic. She is told by the new Captain that, whether they are or not, is not what matters, but if she is loyal to him. T'Pol says that she is, as he is currently in command of Enterprise, which Archer responds by being glad they "can agree on something". (ENT: "In a Mirror, Darkly")
When she hears Archer explain the history of the shotgun he displays, T'Pol asserts her believe that she is not a slave, which Archer refutes that as a Vulcan, she is, a fact she should never forget. (ENT: "In a Mirror, Darkly")
After being quired as to whether or not Enterprise has entered Tholian space, T'Pol answers that they most likely already had, due to the frequency in which the Tholians Annex nearby star systems. She is then given a piece of technology, and ordered by Commander Archer to inform him when the encoded warp signature is detected. (ENT: "In a Mirror, Darkly")
T'Pol expresses her desire to leave, when she is informed that she will be promoted to first officer, which comes as a surprise to the Vulcan, as Major Malcolm Reed was next inline for the position. She is told that Archer feels that Reed is capable enough, but does not follow orders and clearly has his own ambitions. When she states that Archer has made no effort to hide his hatred of Vulcans, he says that it was his way of saying thank you to her species, for without their technology, the Empire could not have made it's initial expansion. (ENT: "In a Mirror, Darkly")