The thunder boomed above Moscow's hot, rain-lashed streets as protesters gathered for the biggest demonstration since Vladimir Putin's inauguration over a month ago.

But the weather couldn't keep tens of thousands of people away.

The flags of communists, nationalists, and liberals waved above the crowds.

It's a disparate movement, united in their hatred of Russia's corruption, and the man they blame for an autocratic political culture - Vladimir Putin.

But how do you get rid of a president who's just won another 6 years in power?

It's the dilemma facing an opposition wanting to show its momentum hasn't weakened.

They face a Kremlin less tolerant than before the elections.

"#hello1937" was the twitter hashtag trending as police burst into the homes of opposition leaders on Monday, a reference to 1937, the worst year of Jospeh Stalin's abuses.

While Vladimir Putin is certainly no Stalin, he's showing little patience for Russia's opposition.

The police searches, it seems, were designed to intimidate the protest movement, and stop Alexei Navalny, Sergei Udaltsov, Ilya Yashin, and Ksenia Sobchak from attending Tuesday's demonstration.

They were told to come in for questioning as the rally was getting underway.

And then there are the hugely increased fines for illegal protests. Roughly $9,000 for normal attendees, and $18,000 for organisers.

Putin signed them through on Friday, against the the wishes of some of his own politicians, and the Kremlin's human rights council.

The punitive move has been criticised by the US State Department, and is of course an outrage for the protest movement.

The Russian government insists they are in line with European norms.

But the people who braved the weather on Tuesday (and fear they could fall foul of the new fines) were defiant.

Speaking to Al Jazeera, one man said "The laws that are being adopted now are being made by people who don't love our country, our children, or themselves. And the point of what is going on here is to stop these people."

Another protester said that the post-election mood is different. "Before when we were going to the rallies, we were worried because of the illegitimate elections and we requested a new vote. Now we realise this illegitimate authority is making decisions which break all the rules."

Putin may be back in the Kremlin, but Russia's protest movement won't give up.

A long summer of action is being promised.