Toshiko Sato
Toshiko Sato
Played by Naoko Mori
Appearances: Series 1, Series 2

"It's worth the risks - to protect people!"

Toshiko Sato was a computer genius and took on the role of the technician of the team, but occasionally used her skills in medical training as and when they were needed. Born in the UK, she went to live in Osaka, Japan when she was two, returning to the UK again in 1986.

One of the greatest challenges Toshiko faced during her time at Torchwood was when she was given a necklace by an alien woman going by the name of Mary. The artifact enabled her to hear people's thoughts, and, whilst using it, she was horrified to learn that Gwen and Owen were having an affair, and to finally hear what people thought about her. This new-found knowledge eventually led her to destory the necklace with the help of Jack, after she realised that sometimes it's best to not know.

It was an image of her mother that convinced Tosh to help Owen open the Rift, although she showed regret afterwards.

Toshiko was good friends with everyone on the team,sharing Gwen's sense of morality. However, it was frequently hinted that she had deeper feelings for Owen, as she held closely the memory of them sharing a kiss on New Year's Eve.

Toshiko and Tommy
"Jack, you saved me. You showed me all the wonders of the universe and all those possibilities, and I wouldn't have missed it for the world. Thank you. And Owen, you never knew! I love you. All of you. And I hope I did good."

She was unfortunately killed after being shot by Jack's brother, Gray. Jack, Gwen and Ianto later found a video message recorded by Tosh, in which she thanks Jack for the experience and tells them all that she loves them.