Crossover Fanfiction Rec

So, I've stopped watching Downton Abbey two seasons ago. But as soon as I saw this crossovery, I knew I'd read it, and did with ever greater joy, for verily, idea and execution are golden.

Tony Stark Meets an Extremely Unimpressed Time Traveler, or, Thomas Barrow Makes a Surprisingly Good 21st Century Butler (87671 words) by Alex51324
Chapters: 3/3
Fandom: Downton Abbey, The Avengers (Marvel Movies)
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Relationships: Thomas Barrow/Tony Stark
Characters: Thomas Barrow, Tony Stark, Steve Rogers
Additional Tags: Time Travel, Butlers, Crossover
Summary:

In which Tony Stark ditches a boring party, makes an addition to the household staff, throws a much better party, and tries not to sexually harass his new butler.

Or,In which Thomas Barrow has a little trouble getting home from the pub, is generally unimpressed with many aspects of the 21st century, never thought of himself as a conservative dresser before, and may or may not be falling in lust with his new employer.

tl:dr: Thanks to time travel, Thomas Barrow becomes the Avengers' butler.

The one thing you have to handwave is that Downton Abbey is actually referenced in Iron Man III, complete with clips (Tony's chauffeur/bodyguard Happy Hogan is a fan), but otherwise, this is perfect. Not least because it uses the ensemble well, not just the two main characters, and has everyone in character. It's funny and touching in turns and the dialogue is golden.