SELECT "First broadcast" FROM table_25911 WHERE "Seans team" = 'Peter Serafinowicz and Johnny Vegas'
What was the first broadcast date of the episode in which Sean's team is made up of Peter Serafinowicz and Johnny Vegas?
CREATE TABLE table_25911 (
    "Episode" text,
    "First broadcast" text,
    "Seans team" text,
    "Daves team" text,
    "Scores" text
)