Bright and chatty here — if you’re hunting for a specific Katherine Parkinson ‘revealing’ scene, the fastest, safest bet is to trace the show or film first. If the clip is from 'The IT Crowd', start by checking services that legally carry that series in your country; sometimes it's on Netflix, sometimes on Amazon Prime Video, and in the UK episodes show up on Channel 4’s All 4 or BritBox. If it’s from another title like 'The Boat That Rocked' or 'Humans', those have moved between services over the years too.
I usually open JustWatch or Reelgood, type Katherine Parkinson or the specific episode name, and it tells me current streaming or buy/rent options. If you only want the short clip, official YouTube channels or the network’s site sometimes host scene highlights — but expect regional locks. Buying an episode on iTunes/Google Play or renting on Prime Video is the most direct legal route. I once spent more time hunting a five-minute gag than the gag lasted, but watching the whole episode made the joke land better — worth it in my book.