Britney Spears celebrated Halloween by staging a small fashion show inside her $11.8M Calabasas mansion for the viewing pleasure of her captive 42.4M Instagram following.

In the first of three videos the 41-year-old Grammy winner posted on Tuesday night, she flashed substantial under-boob cleavage while wearing a sheer black dress with sexy cut-outs.

Britney – whose third husband Sam Asghari filed for divorce from her in August – modeled the mesh creation while grooving along to Janet Jackson‘s 1993 song You Want This.

Spears then changed into a mini-dress featuring a silver sparkly top while posing in front of her stripper pole.

'Hi!' Britney Spears celebrated Halloween by staging a small fashion show inside her $11.8M Calabasas mansion for the viewing pleasure of her captive 42.4M Instagram following

‘Hi!’ Britney Spears celebrated Halloween by staging a small fashion show inside her $11.8M Calabasas mansion for the viewing pleasure of her captive 42.4M Instagram following

Britney Spears flashes cleavage in sheer black Halloween dress

The semi-retired pop star left little to the imagination in a completely sheer side-split dress featuring three silver chains draped over her naked hips.

Britney was cradling one of her five dogs – a Maltese called Lacey Loo – on her bikini-clad chest in the clip set to J Balvin and Willy William’s 2017 song Mi Gente.

Spears then slipped her slim 5ft4in figure into a red dress exposing her arm, abs, and legs while posing in front of her Christmas tree in a clip set to Madonna‘s 2012 song I’m Addicted.

The Hold Me Closer hitmaker’s critically-acclaimed memoir The Woman In Me has sold 400K copies since hitting shelves one week ago – according to TMZ.

Simon & Schuster paid Britney a $12.5M advance (25% of the net profits) to pen the 288-page tell-all with three ‘collaborators’ aka ghostwriters.

Two people close to the project told the New York Times on Tuesday that author Ada Calhoun ‘helped create the first draft’ and author Sam Lansky ‘was the next to join’ The Woman In Me team.

‘The book was completed with the assistance of Luke Dempsey,’ the insider told the mag of the final author to contribute.

And on Monday, Deadline reported that ‘buyers are circling’ Spears autobiography to make bids on the rights to make a potential limited TV series based on the book.

Dress #1! In the first of three videos the 41-year-old Grammy winner posted on Tuesday night, she flashed substantial under-boob cleavage

She was wearing a sheer black dress with sexy cut-outs

Dress #1! In the first of three videos the 41-year-old Grammy winner posted on Tuesday night, she flashed substantial under-boob cleavage while wearing a sheer black dress with sexy cut-outs

Fashion! Britney - whose third husband Sam Asghari filed for divorce from her in August - modeled the mesh creation while grooving along to Janet Jackson's 1993 song You Want This

Fashion! Britney – whose third husband Sam Asghari filed for divorce from her in August – modeled the mesh creation while grooving along to Janet Jackson’s 1993 song You Want This

Dress #2! Spears then changed into a mini-dress featuring a silver sparkly top while posing in front of her stripper pole

Dress #2! Spears then changed into a mini-dress featuring a silver sparkly top while posing in front of her stripper pole

Dress #3! The semi-retired pop star left little to the imagination in a completely sheer side-split dress

The dress featured three silver chains draped over her naked hips

Dress #3! The semi-retired pop star left little to the imagination in a completely sheer side-split dress featuring three silver chains draped over her naked hips

Fluffy accessory: Britney was cradling one of her five dogs - a Maltese called Lacey Loo - on her bikini-clad chest in the clip set to J Balvin and Willy William's 2017 song Mi Gente

Fluffy accessory: Britney was cradling one of her five dogs – a Maltese called Lacey Loo – on her bikini-clad chest in the clip set to J Balvin and Willy William’s 2017 song Mi Gente

Dress #4! Spears then slipped her slim 5ft4in figure into a red dress exposing her arm, abs, and legs while posing in front of her Christmas tree in a clip set to Madonna's 2012 song I'm Addicted

Dress #4! Spears then slipped her slim 5ft4in figure into a red dress exposing her arm, abs, and legs while posing in front of her Christmas tree in a clip set to Madonna’s 2012 song I’m Addicted