Frobisher

Frobisher was a Whifferdill, a shape changer who travelled with the Sixth Doctor and Peri and then the Seventh Doctor for some time. He also encountered the Eighth Doctor.

Early Life
Frobisher became a private invastigator. He was enemies with Dogbolter. Frobisher was once married to another Whifferdill named Francine. Francine left him as she believed she was a better detective than him.

Meeting the Doctor
Frobisher first met the Sixth Doctor when he was calling himself "Avan Tarklu". He came across the Doctor when Dogbolter, placed a bounty on the Doctor. After infiltrating the TARDIS, instead of turning the Doctor in for the money, Tarklu decided that he liked the Doctor and helped him against Dogbolter. He then joined the Doctor on his journeys. He assumed the name of Frobisher because he felt that it sounded British and thought that the Doctor would like that. (DWM: The Shape Shifter)

Frobisher took on a case to investigate Arthur Gringax. (BFA: The Maltese Penguin)

Frobisher and the Doctor visited Peri Brown's desendants several times. (DWMS: The Age of Chaos)

Frobisher ran a bar later, having morphed into the form of a human. He met the Eighth Doctor there but did not recognise him. He talked with the Doctor trying to find out why he looked so sad. When a robot called Zalda entered the bar threatening to blow herself up, the Doctor convinced her otherwise. Frobisher then called for drinks on the house. When everyone had left the bar apart from his wife Caralla who worked there, he morphed back into his penguin form. (DWM: The Flood)

Forms
Frobishers oringinal form is humanoid, pale yellow in color, three to four feet in height, with a round, featureless head, and wearing spectacles. After Francine left him he adopted the form of a Penguin as she had been found of that shape. He did this to remember her. Frobisher often adopted the form of several species of penguin. (DWM: The Shape Shifter)
 * Frobisher temporairily took on the form of the Doctor in order to investigate a murder. (A penguin detective would be shocking.) (BFA: The Maltese Penguin)

Key Life Events

 * Marries Francine.
 * Meets the Doctor and joins him on his travels. (DWM: The Shape Shifter)
 * Adopts the name Frobisher. (DWM: The Shape Shifter)
 * Leaves the Doctor. (After DWM: The World Shapers)
 * Rejoins the Doctor. (BFA: The Maltese Penguin)
 * Meets Peri's decendants. (DWMS: The Age of Chaos)
 * Leaves the Doctor. (DWM: A Cold Day in Hell)
 * Marries Cardella.
 * Unknowingly meets the Eighth Doctor. (DWM: Where Nobody Knows Your Name)

Behind the Scenes

 * Frobisher has only ever appeared in audio, book and comic adventures.
 * Robert Jezek is the voice of Frobisher who is given an American-Brooklyn style accent, he does this in BFA: The Holy Terror and The Maltese Penguin.
 * Frobisher was a companion of the Doctor before Trial of a Time Lord but is absent during the course of it. This suggests he left the Doctor but then rejoined him after as he appears in The Maltese Penguin.