| Underground burial chamber |
| Pioneering underground publication of the 1960s |
| Acting, probably |
| Amazon tablet (Yeah, I probably should have included this as part of the theme, but I couldn't come up with a suitable answer.Sue me.) |
| Paris underground system |
| Announcement that probably goes unheard on a redeye: Abbr. |
| American lake every constructor is sick of cluing, and "American lake" was probably enough to give it to you, so screw it |
| About 600 miles of underground passages near Rome |
| If it sounds too good to be true, it probably is," for one |
| Ancient underground tunnel |
| One of the founders of the underground comix movement: 2 wds. |
| A1: "They're probably ___ him as we speak. |
| An animal whose eggs you'd probably never eat for breakfast." "___ |
| Paris underground |
| Trains underground |
| Underground" director Kusturica |
| Pledge, probably |
| A castaway probably has one |
| ABA member, probably |
| What a couch potato probably holds |
| Coffin of the Underground Railroad |
| Child actor with a pizza-themed Velvet Underground cover band |
| Member of an underground colony |
| Software versions that probably have bugs |
| Part of an underground network |
| NYC underground system |
| Ambulance rider, for short |
| Gr. underground movement in W.W. II |
| One-named singer with the 1960s Velvet Underground |
| President who probably wishes he never said, "It depends upon what the meaning of the word 'is' is": 2 wds. |