Danny and SJ plot the blind side of the season, while the housemates are tortured in a series of cruel tasks

The Big Brother housemates have been left gobsmacked by a ruthless power play as alliances start to blur among contestants.

The “biggest blindside of the season” is pulled off in the shrinking Big Brother household, with a furious exit leaving one contestant hanging his head in shame (and in potential need of a bodyguard).

In all the excitement of scheming and back stabbing, Danny spends the entire episode talking with his mouth full again, which is putting me on edge more than it ever has this gloomy Monday.

I’m seriously considering starting an angry online petition over it.

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I’ve seen inside Danny’s mouth more this episode than I saw outside my own house over the weekend.

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Elsewhere, the housemates are split into two distinct groups defined by party food: one, a meal of frozen sausage rolls and spring rolls. The other, a lavish cocktail party spread of fine seafood and decadent desserts.

It’s like pres in your teens vs. dinner parties in your 30s where everyone talks about their kids and you want to gouge your own eyes out.

We start with Danny and SJ living it up in the “executive suite”, which is just the panic room with a roadside motel makeover.

Big Brother makes a point of telling us it has been designed with “no expense spared”, with the cameras zooming in on bundles of stale Ferrero Rochers and one of those stick-diffuser thingies from Kmart.

Luxury: Big Brother style.

They learn as “heads of house”, they’re allowed to down bottles of Passion Pop and play pranks on their pals in the main area of the house. Sign me up!

Danny doesn’t drink, so SJ polishes off the bottle on her own and gets to work bossing everyone around. She forces the people who evicted her to strip down and jump in the pool, vowing to punish them further in the coming days. Being drunk on $5 sparkling and power is a dangerous combination.

The next morning brings more opportunities to mess with the others, and they eventually learn they’ll be hosting a “cocktail party” with the housemates who can pass their cruel tests.

It’s all too much for Danny, who spends the morning looking like his face is going to explode with happiness.

It’s the Breakfast at Tiffany’s eye mask for me.

First up is Adriana, who must face her greatest fear: Goats cheese. The horror.

(I have a similar fear of full cream milk, if you get me, so I’m with her on this one.)

She polishes off the platter of doom with the utmost grace and finesse.

What the DJ sees when you’re drunk singing along at the club after a tactical vom.

What other cars see when your head’s out the taxi window at 3am.

Mary has to gift wrap a giant teddy bear, Sid has to play charades, Ari has to put sticky notes all over his face and Christina has to define what “Let sleeping dogs lie” means. It’s all very light, fun, and delightfully humiliating for the housemates.

All until Tilly is called in and forced to complete the most vile of challenges ever aired on national television.

Big Brother may even have a lawsuit on its hands.

She has to …

Eat …

A …

BANANA.

We hope they have on-set psychologists.

A true hero in the face of adversity, Tilly completes the task and wins access to the cocktail party. She’ll be joined by Adriana and Marley, while Ari is selected as the door b*tch.

You’d think being the ruler of the fluffy red rope would be right up Ari’s alley. But it turns out he can’t even judge their outfits or passive aggressively say “Not tonight mate,” and literally just has to stand by the door all night while the others party inside.

But he’s not missing much.

On the other side of the rope, Tilly pours a guava cruiser into a cocktail glass and grimaces as she eats an oyster for the first time, while Danny gives a speech with his mouth full of cake and Marley, Adriana and SJ sit around looking drunk and bored.

Ain’t no party like a Big Brother party because a Big Brother party … leaves you with bits of food-spit on your face after talking to Danny.

It’s the worst cocktail party anyone’s ever thrown and I’d frankly much rather be in the other room eating sausage rolls in my pjs.

It does, however, see a new alliance form in Marley and Danny, who vow to fob off one of their people each to show loyalty to one another.

With that, it wraps up, and the housemates awake to a new challenge of nonsensical rules and unnecessarily complicated instructions.

I scroll Ari’s Instagram until it’s over.

Marley wins and with Danny’s promise fresh in his mind, nominates Christina, Ari and Mary, with the hopes he has the numbers to eliminate Christina.

His plan backfires majorly when Mary – his “safe vote” – reacts by storming off and muttering that it’s “the ultimate betrayal”. Doesn’t he know by now not to piss off a Kalifatidis? He’s dangerously close to a face full of red wine.

SJ and Danny — who is furiously shoving handfuls of Pringles in his mouth — debate what to do with the nominations from their suite, using Cherry Ripes to represent the players.

They decide to backflip on their promise to Marley and blindside Mary.

They share their plan with Christina, Ari and Adriana and scurry off to have a pillow fight in their room.

Marley, determined to save Mary (out of fear for his white clothing), confronts Ari to join his alliance, who ponders the idea with glee. This level of drama is his bread and butter.

Into the eviction zone they go.

SJ’s wrapped up in a pink curtain and somehow pulling it off, and Sonia’s serving edgy glamour in a black dress after a small altercation with a bear.

Sonia: 1, dress-ripping bear: 0.

Look courtesy of Spotlight.

It’s getting way to easy for Sonia to persuade these bozos to turn on each other. A gentle push and tempers rise, with Mary spitting acid while glaring down at Marley and SJ making it clear she’s here to fight.

One by one they vote, where it all rests on Ari’s shoulders. Will he backflip and join Marley’s alliance, voting out his bestie Christina, or will he stay true to his word to Danny?

As the biggest wildcard in the house, it’s impossible to tell.

Alas, Mary gets the most votes, storming out of the house without so much as a wave to Marley.

In the back of the car, she tells the camera Marley “gunned the mob mum down”, like we’re suddenly in an episode of The Sopranos and not a low-rent Aussie reality show.

While the others are gobsmacked by the blindside – the biggest shock of all is Ari opting not to throw his mate under the bus in the ruthlessly shady move we anticipated.

Ari, we expected more from you.