Pickett is a small Bowtruckle who accompanies magizoologist Newt Scamander on his journeys. Unlike other Bowtruckles in Newt's case, Pickett suffers from attachment issues and is prone to catching colds, leading him to prefer riding inside Newt's top coat pocket. In 1926, Pickett traveled with Newt to New York City.

When Newt and Tina Goldstein were wrongfully sentenced to death at MACUSA, Pickett used his natural lock-picking skills to free Newt from his shackles in the Death Cell, enabling their escape. Later, Newt reluctantly traded Pickett to the goblin gangster Gnarlak for information. After Jacob Kowalski knocked out Gnarlak and Newt rescued Pickett, the Bowtruckle expressed his sense of betrayal by sulking and blowing raspberries at Newt.

In 1927, Pickett accompanied Newt to Paris. When Newt and Jacob were trapped in Yusuf Kama's sewer hideout, Pickett picked the lock on the gate to free them. Later at the French Ministry of Magic, Pickett briefly snuck out of Newt's pocket, causing Leta Lestrange to spot them. By 1932, Pickett became an active member of Dumbledore's First Army. He accompanied Newt to the Tianzi Mountains to find a newborn Qilin and later assisted Teddy the Niffler in picking the lock of their cage in the German wizarding prison, the Erkstag, securing their escape.