RuPaul's Drag Race All Stars: Season 2

Season overview

Topic: RuPaul's Drag Race All Stars Season 2.
Constraint 1: Use ONLY provided SYNOPSIS and SOURCES.
Constraint 2: Output ONLY valid JSON.
Constraint 3: No markdown, no asterisks, no headings, no bullet points in the prose.
Constraint 4: overview must be a factual 160-220 word summary.
Constraint 5: primer must be an array of exactly 4 concise bullet points.
Constraint 6: Do not invent details (titles, names, dates, etc.).
[1] TMDB: RuPaul's Drag Race All Stars (2012). Twist on RuPaul's Drag Race. Queens from previous seasons pitted against each other in a wig-to-wig drag battle royale. Most celebrated competitors vie for a second chance.
[2] IMDb: RuPaul's Drag Race All Stars. With RuPaul, Michelle Visage, Carson Kressley, Ross Mathews. Queens from previous seasons in a wig-to-wig drag battle royale.
[3] TMDB Season 1: Top queens from Drag Race seasons 1-4. Lip-synch for their lives to determine which all-star claims the ultimate title.
[4] TVDB: RuPaul's Drag Race and Untucked. Michelle Visage, Carson Kressley, Ross Mathews, celeb guest judges, RuPaul.
[5] Alchetron: Theme songs, Emmy Award info.
Problem: The prompt asks for a summary of Season 2.
Source Check:
Source [1] is the general series overview.
Source [2] is the general series overview.
Source [3] is specifically for Season 1. It mentions queens from seasons 1-4.
Source [4] is for the main series.
Source [5] is general info.
Crucial Observation: None of the provided sources contain specific information about Season 2's narrative arc, cast, or specific plot points. They only describe the general concept of the All Stars series (queens from previous seasons competing for a second chance in a battle royale).
Constraint Check: "You write ONLY verifiable facts that are explicitly supported by the provided SYNOPSIS and SOURCES... If a detail is not in the provided material, you omit it rather than guess."
Drafting the Overview:
Since the sources do not provide specific details for Season