The Avengers Screencaps 45-A Touch of Brimstone(1966)

The most controversal episode, banned in the USA and heavily censored in the UK on it's first showing , although by todays standards it may seem pretty tame. Mrs Peel and Steed join a Hellfire club to uncover another dastardly plot. Emma is crowned the "Queen of Sin" by the party revellers hense this costume(from what I've read designed by Diana Rigg) which would eventually inspire Siouxsie Siouxsie and possibly many dominmatrix's .. the Hellfire club scenario also inspired a major storyline  in the X-Men comics and I imagine will feature in the new X-Men movie prequel .here's a short clip