The Doctor, Ian and Barbara first meet Vicki in the adventure, The Rescue. Vicki is a survivor of a spaceship that has crashed on the planet Dido. The young teenage girl finds herself being menaced by the dangerous Koquillon. The timely arrival of the TARDIS and her crew provides desperately needed aid in her struggles.

At the end of this adventure, the Doctor invites the young girl to join him in his adventures aboard the TARDIS. Vicki quickly fills the void left by Susan's departure, and quickly treats the Doctor as she would her own Grandfather.

For the most part, perhaps due to her youth and inexperience, Vicki never really takes the initiative in her time aboard the TARDIS. She willingly accepts Ian and Barbara's leadership, and when they leave, she gladly gives that role to Steven Taylor.  Eventually we do see Vicki maturing as she travels with the Doctor, and it is actually her who convinces the Doctor to let Ian and Barbara leave with the Dalek time machine at the end of The Chase.

It is only a couple of episodes later that Vicki decides it is her time to leave the TARDIS. Vicki falls in love with the warrior, Troilus, when the TARDIS crew becomes embroiled in the siege of Troy, and decides to stay with him in the past. She eventually passes into legend as Cressida, the name given to her by King Priam.