"Say a name," he urged as Blunt stood soaking wet holding the groceries.
His stunned wife finally muttered Stephen Merchant and Krasinski put the English comedian on notice before running out of the frame.
'What are you doing?' Blunt cried out after her husband.
Krasinski earlier shared a video accepting the challenge to raise awareness for promoting awareness of amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease.
The Office star was sitting next to a small windmill and swore that a coffee mug was the largest container he could find to carry out the challenge.
Blunt then casually walked by and dumped a large bucket of water on his head.
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Hollywood superstar Tom Cruise, 52, and his Mission Impossible 5 director Christopher McQuarrie both accepted a challenge put forth by Hugh Jackaman.
Read more: Ice bucket challenge co-founder dies after drowning
Cruise said they were making donations to the ALS Foundation on behalf of the entire cast and crew before getting drenched.
The actor and director seemed to get more than they bargained for as at least six buckets of water were dumped on top of them.
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"How much more?," Cruise asked as the cold water kept coming.
Mel B also accepted the challenge in a video she shared and challenged Heidi Klum, Victoria Beckham and Nick Cannon to participate.
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Sheryl Crow and Usher also posted videos they joined the long list of celebrities who have taken part in the Ice Bucket Challenge.
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Dave Grohl has also taken the ice bucket challenge to another level with this three-minute video.
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The campaign has been backed by The ALS Association and it involves challengers taking part in the ice water deed within 24 hours of being challenged and donating $10.
Alternatively, if they don't want to take part in the icy challenge they are encouraged to donate at least $100 to an ALS charity of their choice.
- Daily Mail