What happened 

Shares of Genius Brands International (GNUS -0.94%) jumped 18.5% on Monday after the children's entertainment company announced the launch of a new toy line. 

So what 

The first toys based on Genius Brands' Rainbow Rangers series hit Walmart (WMT 1.00%) shelves today. The toys will also be available on Walmart.com and Amazon.com (AMZN 0.58%).

Genius Brands' Rainbow Rangers characters.

Genius Brands' Rainbow Rangers. Image source: Genius Brands.

Mattel (MAT -0.38%) is producing the toys under its popular Fisher-Price brand. Genius Brands is also partnering with a range of manufacturers to make other Rainbow Rangers themed items, such as books and apparel. It intends to support the launch with a national marketing campaign.

"The Rainbow Rangers brand has all of the elements to potentially become a breakout hit and a huge business for Genius Brands," CEO Andy Heyward said in a press release. "A lot of our licensing/manufacturing partners feel the same way, which is why we have hundreds of product [stock keeping units] in virtually every category coming to retail across North America over the next 12 months."

Now what

As a small-cap company, Genius Brands is prone to violent price swings. Over the past year, the stock has traded as low as $0.052 on March 12 to as high as $11.73 on June 4. And even after today's gains, shares are down 85% from those highs. 

Investors should expect Genius Brands' stock to remain highly volatile in the days and weeks ahead.