Transformers: Rescue Bots Academy S01E25 - About a Rock
Summary:
Heatwave brings back what he thinks is a sample from an asteroid, and blames the Recruits when it disappears. While searching for it to clear their names, the Recruits quickly discover that the "rock" is actually an alien - and it's loose in the Headquarters!
Transformers: Rescue Bots Academy S1E25 Screenshot