Number One is the pit bull terrier who keeps the retired Jean-Luc Picard company at his family vineyard in La Barre, France, at the end of the 24th century.
Number One is Jean-Luc Picard's dog, a pit bull who lives with the former admiral at Château Picard in 2399. His name echoes the traditional nickname that Picard used for his first officer, William Riker, aboard the Enterprise.
The dog is introduced in Remembrance, the first episode of Star Trek: Picard, where he roams the vineyard, turns up in Picard's dreams and is spoken to in French by his owner. He is seen again at the château in the early part of the first season, before Picard leaves Earth aboard La Sirena.
Number One was played by a rescue dog named Dinero. The breed was chosen in part because Patrick Stewart is a well-known supporter of pit bull adoption.