Arastoo Vaziri (Season 4–) is a lab assistant first appearing in the episode "The Salt in the Wounds".He is one of the interns who came to the lab in the absence of Zack Addy.Originating from Iran, he is a devout Muslim and prays five times a day.

While the language spoken at home while he was growing up would most likely have been Persian or English, as a devout Muslim he would probably have some knowledge of Arabic anyhow and it is entirely possible that he studied Arabic academically.

In the fourth-season finale, Arastoo was re-imagined as a potential buyer of Booth and Brennan's night club. It’s a privilege to be able to serve this victim, to show him the care and love that was so absent that day.” Arastoo is often the opposite of Bones (and similar to Angela, another artist) in investing the victim with humanity at all stages, and feeling empathy for their plight, as in "The Survivor in the Soap" or "The Signs in the Silence" (Which saw the team deal with 'live' evidence in the form of teenage abuse victim Amy Shenfield, Arastoo being particularly moved when X-rays revealed the extent of abuse Amy had been subjected to).

Arastoo shows a high level of proficiency with nunchaku whilst assisting Hodgins in an experiment, and in his first appearance speaks of the 'quips' he endured from "the First Battalion, 9th Marine Regmient, Regimental Combat Team One" in a manner which suggests that he himself was a member. Those horrible men who hijacked those planes hijacked my religion that day, too. In The Bod in the Pod it is discovered that he writes poetry in Farsi and at least one of the poems is dedicated to Cam.

In the sixth-season premiere it is revealed he switched majors from Forensic to Cultural Anthropology and is interning at the Baghdad Museum. In The Pinocchio in the Planter, Wendell mentions that Arastoo comes from a wealthy family. At the end of that episode we also find out they started seeing each other some time shortly prior.

He played a fairly major emotional role in the season 8 episode 6 The Patriot In Purgatory. In the same episode, Arastoo admits to Hodgins that he is a political exile and can never go home again.

He made a speech on the 9/11 terrorists' religion and his own. In 1997 while in his first year of university, Arastoo had published his poems on an underground press, believing the Khatami regime to be more accepting of them.

Being eighteen, his poems were about love, freedom, sex and democracy.

In Beautiful Day in the Neighborhood, he slips up, and his secret is revealed to the team (and the audience). In The Devil in the Details, Vaziri says he served as a military translator in Iraq, where he killed an insurgent while defending his life after surviving an IED. What is not explained is why Vaziri, from Iran, would serve as an interpreter in Iraq.

When asked if she noticed anything strange about Arastoo's accent, Brennan says she thought it was odd that an Iranian would speak English with a Jordanian accent, but she felt that was his business. Iranians speak Persian, whereas Iraqis speak Arabic, although it is possible he is trilingual.