The untold origin story of Optimus Prime and Megatron, better known as sworn enemies, but once were friends bonded like brothers who changed the fate of Cybertron forever.

A 2-part episode from the 4th season of Transformers: Robots in Disguise (subtitled Combiner Force for the 4th season).

The Space Shuttle returns to earth, but some of the equipment brought back on it begins to behave strangely. Scientists are unsure what is happening, and decide to take all necessary precautions.

The Metaliens, alien robots intent on galactic domination, encounter a major setback. Their enormous Space Saucer, 'Compromise', enters a black hole in a strange, uncharted region of Space, and collides with another craft – sending the Kleptonite Ball, their precious cargo and the key to Universal Conquest, hurtling to a planet inhabited by primitive life forms: Earth. Having materialised in a bar, the Ball variously functions as a Christmas tree decoration, a bathroom ornament, and a fortune-teller's prop. The Metaliens must retrieve the Kleptonite Ball if their mission is ever to succeed. And that's when their problems really begin…