Over the past 56 years, Doctor Who has taken the Doctor around the universe with sorts of companions. But for better or for worse, the Doctor's traveling buddies are usually everyday human beings from the era in which their series premiered. However, the show's vast expanded universe of books, comics and audio stories often use their lack of budgetary restrictions to shirk these limitations and create unique companions from across time and space. And no one exhibits this trend more than the shape-shifting alien penguin known as Frobisher.
Created by Steve Parkhouse and John Ridgway in 1984, Frobisher was the Sixth Doctor's primary traveling companion in the ongoing comic strips published within Doctor Who Magazine. The feathery alien proved to be one of the Doctor's best companions and one of the most popular spin-off media characters in the franchise, having maintained a steady presence throughout comic books and audio stories ever since.
Frobisher was a "Whifferdill," an alien species of shape-shifters whose native appearance was a pale yellow human-shaped creature with a featureless, round head. Despite being able to change into anything he can imagine, Frobisher preferred to maintain the look of a cartoonish penguin as his default appearance, and Frobisher traveled with both the Sixth Doctor and the Seventh Doctor in this form.
Before he met the Doctor, Frobisher went by the name "Avan Tarklu" and grew up in poverty on his species' home planet, Xenon, where he barely made ends meet as a private detective and a con man in the 82nd century. When a local alien crime lord named Dogbolter placed a bounty on the Sixth Doctor's head, Tarklu helped the technicolor Time Lord escape and became his traveling companion, adopting the name "Frobisher" and the form of a penguin to better fit in.
Frobisher joined the Sixth Doctor for many adventures in time and space, and became one of the time traveler's most trusted friends. The feathery alien saved the Doctor from drowning, helped him unravel a zoological conspiracy and defeat the Master's army of Autons, and even met one of the Sixth Doctor's other traveling companions, Peri Brown, who traveled with this version of the Time Lord on television.
Frobisher was the Doctor's de facto comic book companion in Doctor Who Magazine for the rest of the '80s and the beginning of the '90s, but even after he stopped regularly appearing in its comic-strips, the shape-shifting bird has continued to pop up across the franchise's various media to this day. One of his most significant roles was in the special 50th Anniversary twelve-issue comic book miniseries Doctor Who: Prisoners of Time, in which an old enemy of the Doctor kidnapped many of the Time Lord's most trusted allies.
Contacted by the Tenth Doctor, Frobisher took the form of companion Peri Brown so that he was kidnapped and imprisoned in her place. The alien penguin was able to use his abilities to escape the cell designed to hold Peri, free the other imprisoned companions and tell the Doctor's first eleven incarnations where they were being held captive. Due to Frobisher's unique skills, the Doctors were able to save their friends and defeat their old enemy.
After the Doctor regenerated into his Seventh Incarnation, Frobisher found that he was needed less and less and retired from his travels with the Doctor to live a life of peace and luxury on an alien planet in the 41st century. There, the penguin lived in peace and helped the locals as a private investigator whenever they needed him.