A Muppet's revenge! Kermit is left dumbfounded as he spots Castle star Nathan Fillion sneaking out of Miss Piggy's trailer after rendezvous

They split just a month ago so it's no surprise tensions are still strained between Kermit the Frog and Miss Piggy.  

And after the amiable amphibian's rumoured new girlfriend was revealed this week, Miss Piggy is wasting no time in hitting back at her ex, taunting him with a fling of her own.

Unfortunately for Kermit, the object of Miss Piggy's affections was fellow ABC actor Nathan Fillion who he spotted sneaking out of the glamourous blonde's trailer in a behind-the-scenes clip from his new show.

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Scandalous: Kermit is shocked to see Castle star Nathan Fillion sneaking out of Miss Piggy's trailer in behind-the-scenes clips from an ABC promo for The Muppets

Scandalous: Kermit is shocked to see Castle star Nathan Fillion sneaking out of Miss Piggy's trailer in behind-the-scenes clips from an ABC promo for The Muppets

Shocked: The amiable amphibian is lost for words after seeing the actor making a quiet exit 

Shocked: The amiable amphibian is lost for words after seeing the actor making a quiet exit 

In an extended promo for The Muppets, the fuzzy little guy is seen looking through a script with a cast member when they are interrupted by the sound of a door shutting.

The handsome Castle actor is seen with his shirt hastily buttoned and his hair slightly ruffled as he tries to slink out of the trailer unnoticed.

After appearing a little sheepish, Nathan, 44, fixes his gaze ahead and walks by the duo briskly with a brief 'Morning!'.

After the awkward exchange Kermit looks off into the distance in disbelief and lets out a loud sigh.

Sneaking out: Kermit is seen looking through a script with a cast member as Nathan starts to make his quick exit

Sneaking out: Kermit is seen looking through a script with a cast member as Nathan starts to make his quick exit

Making a run for it: The 44-year-old actor tries to back down the steps quietly the morning after

Making a run for it: The 44-year-old actor tries to back down the steps quietly the morning after

The exes revenge: Kermit can't quite believe what he is seeing 

The exes revenge: Kermit can't quite believe what he is seeing 

The Muppets kicks off on September 22 and Kermit explains in the clip 'We're super excited for our new show on ABC and they brought all the stars to kick it off,'

'Our new show is not like anything you've seen us do before,' Miss Piggy reveals.

'You are going to see behind the scenes of The Muppets.'  

It's been less than a month since Kermit and Miss Piggy split after 40 years together.  

Walk of shame: Nathan looks rather sheepish as he slinks out of the trailer emblazoned with Miss Piggy's name 

Walk of shame: Nathan looks rather sheepish as he slinks out of the trailer emblazoned with Miss Piggy's name 

Resigned: Kermit exhaled sadly at the end of the clip which promotes the show premiering on September 22

Resigned: Kermit exhaled sadly at the end of the clip which promotes the show premiering on September 22

And this week People confirmed that he has already found a new love in the form of a doe-eyed brunette named Denise.

But Kermit has denied it is anything more than platonic as he tweeted: 'It is true that I am dating again,

'However, at this time no one woman – pig or otherwise – is my official 'new girlfriend.' We are simply close friends.'

However, a source told People that Denise is 'always stopping by the set of Up Late' - the show-within-a-show which forms the basis of ABCs new The Muppets docuseries. 

That was quick: Kermit moved on very quickly from his split with Miss Piggy and is now dating a brunette named Denise (pictured)

That was quick: Kermit moved on very quickly from his split with Miss Piggy and is now dating a brunette named Denise (pictured)

But Miss Piggy is not taking it lying down as the saucy blonde also enjoyed a smooch with another handsome human man, Topher Grace, the star of hit US sitcom That ’70s Show. 

And on top of that she has also been linked to Miley Cyrus' ex-fiancé Liam Hemsworth.  

The Muppets premieres on September 22 at 8pm ET on ABC in the U.S. 

Another hunk: Miss Piggy has also been linked to Liam Hemsworth after working together on set

Another hunk: Miss Piggy has also been linked to Liam Hemsworth after working together on set

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