Continuity mistake: When Agnes and Dermot jump off the bridge, Grandad is a fair distance away in the boat. When Buster jumps just a few seconds later, Grandad's boat is in position for Buster to land in it. (01:14:15)
Suggested correction: That's because Mrs Brown and Dermot jump into the river scene was done in slow motion and Grandad was only 5 or 6 ft away from them.
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Continuity mistake: When the Russian crushes the fruit at Mrs. Brown's stall, a bit of pulp lands on her jumper, which then disappears when she hits him with the mallet. (00:30:25)
Suggested correction: That's because she bends down to pick up the mallet and as she bends down it naturally falls off her pink cardigan.