The official trailer for the forthcoming fourth season of Netflix serial killer thriller YOU has arrived - and it features scenes filmed at Knebworth House.

Penn Badgley returns as Joe Goldberg in season four of YOU and this time the murderer has relocated to London, assuming the identity of bearded university professor Jonathan Moore.

The Comet: Penn Badgley as Joe Goldberg/Jonathan Moore in season four of Netflix thriller You.Penn Badgley as Joe Goldberg/Jonathan Moore in season four of Netflix thriller You. (Image: Courtesy of Netflix © 2022)

With the latest Netflix poster on Instagram taglined 'Social climbing can be murder', Joe mixes once again with the upper class - with Hertfordshire stately home Knebworth House figuring prominently in the first trailer.

You can watch the official Netflix season 4 part 1 trailer for YOU below.

This paper revealed last month that Knebworth House was one of the filming locations of the eagerly awaited latest run of YOU.

Included in the just released Netflix YOU trailer is a group of wealthy socialities playing croquet on the sunken lawn at Knebworth House - and a "murder among the elite" takes place at the estate during the series. 

Among those at the Gothic mansion are Tilly Keeper as Lady Phoebe and Ghosts star Charlotte Ritchie as her good friend Kate. 

The Comet: Tilly Keeper as Lady Phoebe and Charlotte Ritchie as Kate in season 4 of You. This scene of the Netflix series was filmed at Knebworth House.Tilly Keeper as Lady Phoebe and Charlotte Ritchie as Kate in season 4 of You. This scene of the Netflix series was filmed at Knebworth House. (Image: Courtesy of Netflix © 2022)

The trailer voiceover by Joe says: "Laying low is imperative.

"Turns out teaching's fun and London's not so bad.

"I fell in with the most insane, damaged peope on Earth."

The trailer later features a TV news report on the so-called 'Eat the Rich Killer' striking again with an aerial shot of Knebworth House shown on screen.

The newsreader says: "Police are continuing to investigate a second murder among the elite."

The Comet: Charlotte Ritchie as Kate in Netflix series YOU.Charlotte Ritchie as Kate in Netflix series YOU. (Image: Courtesy of Netflix © 2022)

This time, however, the tables have turned and killer Joe is also being stalked by someone - the predator becoming the hunted. 

Joe turns detective to work out who the other murderer in town is.

“I ran away from all this,” says Badgley’s Joe in the trailer.

“But one of you is watching me. One of you is hiding in plain sight. So, who are you?”

The Comet: Tilly Keeper as Lady Phoebe and Penn Badgley as Joe in season four of YOU. Tilly Keeper as Lady Phoebe and Penn Badgley as Joe in season four of YOU. (Image: Courtesy of Netflix © 2022)

The new series of psychological thriller YOU launches on streaming site Netflix next month, with season four split into two batches.

Part one of YOU's latest season can be seen from Thursday, February 9, with the second part arriving on Netflix a month later on March 9.