![]() |

| Adventures into the Unknown #21 | ||
| American Comics Group, 7/51 | ||
| Paul Gattuso, Lin Streeter, Pete Riss, | ||
| Edvard Moritz and Charles Sultan art | ||
| Ken Bald cover | ||
| Books | CGC Label | CGC Total | Avg. Grade | 10 | 9.9 | 9.8 | 9.6 | 9.4 | 9.2 | 9.0 | 8.5 | 8.0 | 7.5 | 7.0 | 6.5 | 6.0 | 5.5 | 5.0 | 4.5 | 4.0 | 3.5 | 3.0 | 2.5 | 2.0 | 1.8 | 1.5 | 1.0 | 0.5 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 BOOK | Universal | 25 | 6.42 | 0 0.00% | 0 0.00% | 0 0.0% | 1 4.0% | 1 8.0% | 3 20.0% | 0 20.0% | 0 20.0% | 2 28.0% | 4 44.0% | 1 48.0% | 3 60% | 1 64% | 3 76% | 1 80% | 0 80% | 2 88% | 0 88% | 1 92% | 1 96% | 0 96% | 0 96% | 0 96% | 0 96% | 1 100% |
| 1 BOOK | Signature | 2 | 6.25 | 0 0.00% | 0 0.00% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 0 0.0% | 1 50% | 0 50% | 0 50% | 0 50% | 0 50% | 1 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% | 0 100% |
| Adventures into the Unknown #21 (1951, American Comics Group) CGC Universal Grade Distribution | ||||||||||||||||||||||||
| 0% 0 10 | 0% 0 9.9 | 0% 0 9.8 | 4% 1 9.6 | 4% 1 9.4 | 12% 3 9.2 | 0% 0 9.0 | 0% 0 8.5 | 8% 2 8.0 | 16% 4 7.5 | 4% 1 7.0 | 12% 3 6.5 | 4% 1 6.0 | 12% 3 5.5 | 4% 1 5.0 | 0% 0 4.5 | 8% 2 4.0 | 0% 0 3.5 | 4% 1 3.0 | 4% 1 2.5 | 0% 0 2.0 | 0% 0 1.8 | 0% 0 1.5 | 0% 0 1.0 | 4% 1 0.5 |
| cgcdata.com, last updated September 16, 2025 | ||||||||||||||||||||||||