Image copyright Getty / Reuters Image caption Denzel Washington stars in The Equalizer, Lily James in Mamma Mia! Here We Go Again

When it was released on Friday, Mamma Mia 2 was all set to be the biggest film of the weekend, if not the summer.

But a spanner has been thrown in the works at the US box office, in the shape of Denzel Washington.

The Equalizer 2, the follow-up to the 2014 original, raced past Mamma Mia! Here We Go Again to claim the top spot.

The action sequel took an estimated $35.8m (£27.2m), inching past Mamma Mia's $34.4m (£26.1m).

But these weren't the only two sequels in town.

No fewer than eight of the top 10 films over the weekend were follow-ups, confirming that summer truly is sequel season for cinema.

See if you can spot the two odd ones out below:

Weekend box office - US

Image copyright Pixar Image caption The first Incredibles movie was released in 2004

1. The Equalizer 2- $35.8 (£27.2m)

2. Mamma Mia! Here We Go Again - $34.4m (£26.1m)

3. Hotel Transylvania 3 - $23.2m (£17.6m)

4. Ant-Man and the Wasp - $16.1m (£12.2m)

5. Incredibles 2 - $11.5m (£8.74m)

6. Jurassic World: Fallen Kingdom - $11m (£8.36m)

7. Skyscraper - $10.96m (£8.3m)

8. The First Purge - $5m (£3.8m)

9. Unfriended: Dark Web - $3.5m (£2.7m)

10. Sorry to Bother You - $2.8m (£2.1m)

Well done if you said Skyscraper and Sorry To Bother You were the only films not to be part of a franchise.

Mamma Mia coming in second place is by no means a failure - the film opened in line with expectations.

Instead, the surprise was the success of The Equalizer 2 - with analysts putting it down to an ethnically diverse audience and keen interest among men.

"It was a surprise to come in at number one in an extremely competitive marketplace," Adrian Smith, Sony's head of domestic distribution, told Variety.

"It really speaks to the power of Denzel, without a doubt."

Its success came in spite of a lukewarm response from critics, one of whom described the film as having a "plot that reads like middle-aged male fantasy".

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