The hosts were rabbits caught in the headlights as they leaked early tries to Louis Rees-Zammit and Hamish Watson, but an impressive uprising followed that troubled the Lions' defence for a spell.
Once that had been subdued, Warren Gatland's men ran riot with Adams helping himself to four second-half tries against the weakest of the provincial sides they will face over the coming weeks.
Adams lifted his total to five touch downs in two starts after also getting on the scoresheet against Japan, placing him in pole position to secure one of the wing slots against the Springboks on July 24.
Scrum-halves Ali Price and Gareth Davies also unpicked the outclassed Sigma Lions before empty stands at Emirates Airline Park, while Owen Farrell completed all eight conversions.
The jury is still out on the 10-12 partnership between Farrell and Finn Russell, but Scotland's maverick playmaker provided thrilling moments of skill to enhance his own Test prospects.
Although Adams ended up with four tries, it was Russell's Scotland team-mate Watson who was named official man of the match after he delivered an all-action display at openside.
And after the cruel misfortune of losing Alun Wyn Jones and Justin Tipuric to injuries in the curtain-raiser against Japan a week earlier, the Lions were relieved to see no obvious casualties go down in Johannesburg.