The fifth season of Stranger Things has sparked global excitement, especially with the arrival of a mysterious new character connected to the dangerous alternate world. One figure capturing attention is an imaginary companion named Mr. Whatsit, who becomes significant due to his link with Mike Wheeler’s younger sister.

Who Is Mr. Whatsit?

Mr. Whatsit is introduced as the imaginary friend of Holly Wheeler, the youngest member of the Wheeler family and sister to Mike and Nancy. Although her mother and teacher dismiss him as a product of imagination, Holly firmly believes he exists. Tensions escalate when Holly is pulled into the Upside Down by demogorgons, leaving her siblings anxious. During the attack that injured their mother, she describes Mr. Whatsit with imagery reminiscent of “Mrs. Whatsit” from A Wrinkle in Time.

A twist unfolds when viewers learn that the name “Henry” is linked to Mr. Whatsit—revealing that Vecna, portrayed by Jamie Campbell Bower, is connected to this mysterious entity. Karen Wheeler explains that Holly’s imaginary friend resembles a tall man wearing a hat and carrying a pocket watch, gentle in manner yet invisible to everyone except Holly. He once waved at her without showing his face. Later, Holly appears to be speaking to someone at school, prompting her teacher to inform her mother about the unusual behavior, hinting that Mr. Whatsit might be attempting to reappear in her life.

About ‘Stranger Things’ Season 5

Season 5 of Stranger Things premiered on November 27, 2025, releasing its first three episodes. Part two is scheduled for December 25, followed by the season finale on December 31, 2025. The series—created by the Duffer Brothers—features a star-studded cast including Millie Bobby Brown, Finn Wolfhard, Noah Schnapp, Caleb McLaughlin, Sadie Sink, Gaten Matarazzo, Joe Keery, David Harbour, Winona Ryder, Charlie Heaton, Maya Hawke, Cara Buono, and others.