Poor old Theresa May.
Instead of doing her job at prime minister's questions... y'know, answering questions put to her on behalf of the public by their representatives...she fancied herself as a stand up act.
Let's embarrass poor old Corbyn instead of answering difficult questions about Brexit, she thought to herself.
Only she made a bit of a mess of it.
Because when she was checking out Mr Corbyn's Twitter feed to see if she could get herself some forewarning of what he was going to ask her... she found an amusing tweet from a certain Mr Lewis Collins.
Mr Collins, suggesting a question for Jeremy to ask Mrs May, wrote: Does she know that in a recent poll asking who would make a better prime minister, "don't know" scored higher than Jeremy Corbyn.
Ho Ho Ho. Ha ha ha. Point to Mrs May. Right?
Well only very briefly!
Of course Mr Corbyn sat and smiled politely as she said it. Maybe he knew something that, at the time, Mrs May did not.
Mr Collins alerted to the fact that his question had been used... he'd hardly expect that... tweeted his pride at being quoted by her primeminsterness: "Looks like I'm famous", he bragged!
You are, Mr Collins, you most surely are.
Because it turns out that Mr Collins, maybe one of Mrs May's supporters, and a bit of a wit, may find that his 5 minutes of fame will not bring him the kudos he perhaps briefly hoped for.
Y'see, when something like this happens, people rush off to look at one's timeline. And, somewhat unfortunately for everyone except Mr Corbyn, dear old Mr Collins' turned out to be somewhat less respectable than a prime minsiterial script writer might be expected to have.
Well, clearly he doesn't overly care for Poles, as we can see from the Tweet above.
Eastern Europeans in particular have, since Brexit (whatever that means) was announced, have suffered badly at the hands of racists... including one being killed, apparently for speaking Polish to his mate. (Note to Brits going abroad: Always remember to speak the language of the country you're in, even to your Brit mates... Right? Yeah, right!)
But Mr Collins isn't a one trick pony. Oh no, he has other unpleasant strings to his bow. If Mrs May wants some one liners for next week's PMQs she may chose from a range of other prejudices.
For example, another tweet reads "P~ss off, you feminist piece of sh~t". Is Mr Corbyn a feminist?
Then he pictured a zombie and labelled it: "Migrant workers looking for ways to circumvent the Calais wall". Well, at least there are plenty of zombies in the House for her to poke fun at!
He reportedly also tweeted in support of the murdered of Jo Cox. And no one is going to amke any jokes about that.
Now Mr Collins may be perfectly entitled to these views, although, as we said, he may find that his fame as a prime ministerial gag writer will bring as many problems as plaudits...
...but Mrs May should most certainly learn from today's experience that the only way to be safe in these matters is to write her own material.
Mr Corbyn's smile is somewhat more comprehensible now.