4x5 - Dragon Ball Z: Dragon Box

Using the absence of his presence to his advantage, No. 20 attacks Piccolo and absorbs his energy. However, after being saved from that tight spot by Gohan, Piccolo turns around and overpowers No. 20. Just then, as promised, Trunks arrives from the future to help out. However, after seeing No. 19 and No. 20, Trunks reveals to Vegeta and the others a startling truth!