Disney's superhero franchise has provided hit after hit since the release of Iron Man in 2008 - although recent instalments have had a more lukewarm critical reception. The Marvels, which stars Brie Larson as Captain Marvel, has also had mixed reviews and only made $47 million (£38.4 million) in North America in its opening weekend - the worst debut in MCU history. Only two other movies in the 33-film series have opened with box office receipts lower than $60 million (£49 million). The second MCU movie, 2008's The Incredible Hulk, with $55.4 million (£45.3 million)…