Who Do You Think You Are?: Series 21

Season overview

Role: Meticulous television and film archivist.
Task: Produce a JSON object for "Who Do You Think You Are?" Season 21.
Constraints:
Use ONLY provided SYNOPSIS and SOURCES.
No invented titles, names, dates, episode counts, awards, ratings, box-office, viewership, or plot points.
Omit details not in the material.
Style: Original, neutral, encyclopedic prose in plain text.
Format: No markdown, no asterisks, no headings, no bullet points in the prose.
Output: Valid JSON only.
JSON Keys:
overview: Factual 160-220 word summary of this season's narrative arc.
primer: Array of exactly 4 concise bullet points summarizing essential previous lore, character positions, and stakes.
TMDB Synopsis: "Stars delve into their family history to find moving, funny and extraordinary stories."
Source [1]: British genealogy documentary series; celebrities trace ancestry; discovering secrets and surprises.
Source [2]: British genealogy documentary series; aired on BBC since 2004; made by Wall to Wall; regularly attracts more than 6 million viewers.
Source [3]: Cast and crew credits info.
Source [4]: British genealogy documentary series; celebrities trace ancestry; discovering secrets and surprises from their past.
Source [5]: Cillian Murphy news (irrelevant).
Constraint Check: The prompt asks for a summary of Season 21.
Data Check: Looking at the sources... none of the sources mention "Season 21" specifically. They mention the series started in 2004 and is a British genealogy documentary.
Problem: I cannot invent details about Season 21 if they are not in the text. The text only describes the series in general.
Instruction: "If a detail is not in the provided material, you omit it rather than guess."
Instruction: "Write original, neutral, encyclopedic prose... overview: factual 160-220 word summary of this season's narrative arc."
Wait: If I cannot find information about Season 21 in the sources, I cannot write a 160-220 word summary of its narrative arc. If I write a general summary of the series, I am not summarizing the season's narrative arc. However, if I say "Information not provided," I am following the rule "If a detail is not in the provided material