Realize

The second single released from Power Up, "Realize" features increasingly frantic bursts of staccato rhythm guitar and similar rhythm that recalls AC/DC's 1990 hit "Thunderstruck."

Lyrically, this finds singer Brian Johnson vowing to make listener "realize" that AC/DC have the power to produce music that sends a "chill up and down your spine." An alternative interpretation is he is addressing a girl asking her if she realizes he's "got the power to electrify, make or break, or satisfy."

Angus Young and his late brother Malcolm, who died in 2017, wrote the songs on Power Up in the period leading up to 2008's Black Ice. "A lot of them were ideas we had that we knew were good AC/DC ideas at the time, but we just never got around to getting them on record," Angus told Ultimate Classic Rock. "Malcolm and me had a lot of years when the two of us would just be in a little studio, just working away all the time... and in that period we'd so much stuff. When we went to do Black Ice, it was a case of you've got a few boxes of your ideas... [and] we only got [into] box one."