People are claiming sick days to watch Game of Thrones

The highly anticipated return of Game of Thrones might be the reason your colleague or employee has taken the day off work 'sick'.

Premiering at 1pm on Monday (NZ time), the debut episode of the hit fantasy TV show's eighth and final season is one of the most anticipated in modern television history.

"If your workmate calls in sick on Monday, chances are they have a bad case of Westerositis, which will likely repeat for the next few weeks," says TV Tonight blog editor David Knox.

Poking fun at the phenomenon of people throwing sickies to watch Game of Thrones, MediaWorks' digital audio streaming platform Rova posted a joke medical certificate on Facebook.

However, pretending to be unwell to take a day off means you could be in breach of your employment contract and suffer disciplinary measures as a result.

Australian employment lawyer Daniel Stokanoski warns against faking illness to be one of the first to watch the Night King's forces attack Westeros - but concedes that many people will be doing so.

"[Workers] would do this legally through taking leave and illegally by falsely claiming illness," Stokanoski told The West Australian.

"I can definitely say there will be a bigger rate of people taking the day off to watch Game of Thrones because it's a Monday, it's convenient."

Game of Thrones is broadcast in New Zealand on streaming service Neon and Sky TV's SoHo channel.