Need help identifying these little monsters creatures on my cucumber plants. It doesn't look like a beetle but working along side beetles.

Need help identifying these little monsters creatures on my cucumber plants. It doesn't look like a beetle but working along side beetles.

That is a ladybug larvae - don't kill it. It is eating pests, and is a beneficial insect. Are the beetles they were found with ladybugs? that would make sense. But Mexican bean beetles and Cucumber beetles also look like ladybugs, I'll include a side by side comparison picture.
From left to right, ladybug, mexican bean beetle, and cucumber beetle:


From left to right, ladybug larva and mexican bean beetle larvae:


Cucumber beetle larva:

As you can see, the larvae are much easier to distinguish between than the adults are. I would leave the ladybug larvae on the plant, unless you want to spray it. In that case, carefully transport them to a new location, infested with aphids (one without ant farmers is preferable).